There has never been either a legal or moral right in any tradition of freedom of speech throughout history, including the US tradition, to insist that other private parties who disagree with your speech continue to do business with you. The strong US freedom of speech protections are about government action only, and even those have exceptions. Every judgment of this sort has some subjectivity, and that's fine.
If someone dislikes Discord's judgment on that matter, they can switch providers or run their own service. If every viable provider stops dealing with them, that kind of implicit collective judgment and its consequences have always been part of humanity.
Also, most Western countries other than the US do have laws or judicial precedents which define terms like hate speech and provide penalties for engaging in it that are routinely adjudicated and enforced by courts. Even US judges consider hate speech as evidence an aggravating factor in how they handle crimes with hate as a motivation, accept the illegality of incitement to imminent violence, etc.
> There has never been either a legal or moral right in any tradition of freedom of speech throughout history, including the US tradition, to insist that other private parties who disagree with your speech continue to do business with you.
How would that work, practically? Let's say I prefer to get my hair cut by a barber that makes public statements in favor of gender equality instead of patronizing one that publicly advocates for the dynamics of Western society's traditional gender roles. For the sake of this scenario, let's say there's no other relevant difference between the two barbers, except where noted. Should my disfavored barber be able to insist that I shift some or all of my hair care business to them since the reason I'm not using them is their speech? How much of my business should they be able to force?
Would it be any different if I preferred the traditionalist and the one who wanted to force my business were the equality advocate? What if my preferred barber just stayed quiet and it were the one who vocally advocated either view who insisted on my business? What if the business terms of the barber with distasteful speech were worse, and how much worse would they need to be for that difference to outweigh their free speech rights?
None of this seems very plausible to enforce well.
More importantly, who would decide among all these possibilities? That's quite the power of imposing one's views (and financial policies) on others. I'm not sure I trust any government or private regulatory authority with that much control over private lives and livelihoods.
Both sides of that case agreed that the company was choosing to deny its custom wedding cake services to a gay wedding because of the owner's religious beliefs against gay weddings, not because of anyone's speech. In other words, they objected to making a wedding cake because of attributes inherent to who the engaged couple were, not anything that was being said or expressed.
I view it as plenty consistent to forbid businesses which serve the public from choosing not to serve customers based on innate aspects of who they are, like being the same sex or gender as each other, while still allowing them to make such choices in reaction to the customer's speech. Sometimes the line is clear (no speech was at issue in this case), and sometimes it's blurry, but that's absolutely a consistent rule whether or not it's the one you support.
The reason the Supreme Court ruled for the bakeshop was very narrow. The ruling acknowledged that states can constitutionally have non-discrimination laws that apply neutrally to businesses without making available exemptions due to religious beliefs. The ruling was just about the behavior of the Colorado Civil Rights Commission in applying their state law to this case, which the Supreme Court majority viewers as hostile to the owner's religious beliefs and not religiously neutral as the government must be. So it was about religious bias in the government action, only. One member of the 5-4 majority wrote that he might well have ruled the other way had the commission acted neutrally.
The concern expressed by the cakeshop was primarily about making a custom wedding cake for a gay wedding, not the message. Put differently, they wouldn't have made a custom cake for this particular wedding, knowing it was a gay wedding, even if there were no message requested. The ruling was not on free speech grounds.
Anyway, the cakeshop scenario is a bit different in another way: it can be argued to involve expressive activity on the part of the employees who create the custom cake, since it's far more artistic than mechanical, and since they do literally write any requested message with decoration. By contrast, Discord's actions against the customer are simply a choice of which speech by others they choose to allow to flow through the platform they control, plus a statement of their own speech which they choose to put out about their action.
(For what it's worth, they've chosen to partially reverse their ban since we started out discussion, if I understand right.)
If you want to ensure there is a content neutral platform, maybe the best way (at least under US free speech concepts) is to advocate for a government-owned/run Internet group communication platform, just like we have in offline life when you go to the nearby park or plaza to protest, or when you send mail to everyone in your local community through USPS.
Everyone agrees that, in the US, the government can't constitutionally censor that on the basis of content or viewpoint, with a few exceptions such as forbidding child pornography. I'm guessing that platform wouldn't keep getting funding from the politicians if it got too much offensive content, but if it wasn't shut down entirely, they couldn't be selective about which speech to permit.
But that's the thing - not everyone does think less of such people, under the view that only people with privilege can even have the luxury of tuning out the impact of politics on their lives at work, since marginalized colleagues still suffer the impacts of politics daily at the office (or indirectly elsewhere in ways attributable to the actions and inactions of their employer) and they shouldn't be blamed for mixing politics and business when they speak up about it. I realize that's not your view, but it's a plenty common view.
Further, not everyone who wants to keep politics and business separate even agrees on what mixing politics and business means.
Is it politics for a company to go out of its way to make bathrooms explicitly gender-neutral, put pronouns in staff directories, encourage even people who are not trans to indicate their pronouns so that trans people don't feel singled out by doing so, discipline people for persistent or intentional use of the wrong pronouns in the workplace, and cover common trans needs like hormone replacement therapy in the company health insurance plan?
Many people on the right of the US political spectrum would call that politics. Many other people conclude that some good workers happen to be trans and would feel more comfortable working at such employers than at ones with traditional attitudes toward them, meaning that these changes have the apolitical good business consequence of maximizing the ability of the company to attract and retain workers.
Does one have to inquire into the motivation of the employer for adopting these policies to decide if they're mixing politics or business, or just engaging in business?
Lots of subjectivity even on moral rights questions like this.
Though, I will say that my use of the word "enforce" is really only applicable to legal rights, not moral rights, outside of some kind of dystopian enforcement of what people are allowed to think.
If someone dislikes Discord's judgment on that matter, they can switch providers or run their own service. If every viable provider stops dealing with them, that kind of implicit collective judgment and its consequences have always been part of humanity.
Also, most Western countries other than the US do have laws or judicial precedents which define terms like hate speech and provide penalties for engaging in it that are routinely adjudicated and enforced by courts. Even US judges consider hate speech as evidence an aggravating factor in how they handle crimes with hate as a motivation, accept the illegality of incitement to imminent violence, etc.