To some extent this is handled via GPL/AGPL, which gets in the way of companies building a fence around your work and locking you outside. If you use them.
But the general idea that you need a monopoly is wrong. You don't need a monopoly, only scarcity. Monopoly is extreme scarcity but you don't actually need that. Just enough to turn a profit and stay in business.
Redhat makes plenty of money and has a monopoly on nothing. They're just not in the consumer products business. Somebody needs to be the Redhat to Apple's Microsoft.
Realistically Google's business model isn't completely useless here, i.e. make free software to sell services to the users. Or make free software to sell hardware to the users. The problem with Google is that they became too much of a publicly-traded conglomerate and then they get bad incentives to betray the community -- having a monopoly actually makes it worse because it enables abusive behavior.
> Redhat makes plenty of money and has a monopoly on nothing.
Redhat managed to leverage their monopoly on their own trademarks to prevent anyone unauthorized from offering Redhat-branded support services, coupled with the time-bound monopoly on their own updates (because obviously no one gets those until they actually get distributed) that translates into a short delay for other vendors to incorporate those improvements (and longer if any discussion of whether to include them is warranted).
For most purposes these delays are inconsequential, but plenty of customers are willing to pay for the privilege of getting bugs and critical security fixes distributed and deployed ASAP just so zero-day vulns can't become one- or two-day ones (at best).
It's worth noting that this is more a matter of perception than reality, since by far the biggest factor delaying the eventual deployment of updates including critical security fixes is the customer's own internal processes, but it is hard to get a customer to admit that going from a 15-day to a 14-day delay hardly justifies paying a premium.
You're just using a pedantic definition of monopoly that would cause anybody to have a monopoly on something. It's equivalent to saying that no two pieces of real estate are identical so land ownership is a monopoly, even though in practice land is fungible with other land and owning one piece of land is not what anybody means by a monopoly.
Redhat is clearly not the iOS app store or 1970 AT&T.
Trademarks aren't even property, they're a consumer protection mechanism. You nominally can't even sell them, though the restriction is more in theory than in practice.
I'm not being pedantic. Copyrights, trademarks, and patents are all monopolies, and most of their realizable market value is derived from that (more technically, the exclusivity is what enables the conversion of use value to market value).
Trade secrets are an even more extreme case of a monopoly that doesn't even have the expiration dates of patents and copyrights, or the active defense requirement of a trademark.
But the general idea that you need a monopoly is wrong. You don't need a monopoly, only scarcity. Monopoly is extreme scarcity but you don't actually need that. Just enough to turn a profit and stay in business.
Redhat makes plenty of money and has a monopoly on nothing. They're just not in the consumer products business. Somebody needs to be the Redhat to Apple's Microsoft.
Realistically Google's business model isn't completely useless here, i.e. make free software to sell services to the users. Or make free software to sell hardware to the users. The problem with Google is that they became too much of a publicly-traded conglomerate and then they get bad incentives to betray the community -- having a monopoly actually makes it worse because it enables abusive behavior.