> That if unionization is so cleary net positive for most workplaces, then it wouldn’t need any sustained agitation campaigns in the first place.
> As any company that unionizes would near automatically gain a huge competitive advantage.
No, your "observation" has a fundamental flaw: There's no general "net positive for most workplaces," because different groups have different interests.
Unionization is a "net negative" for certain groups (managers, owners) and a "net positive" for others (employees, if done right). That's why there are sustained agitation campaigns against it.
We (especially those with an entrepreneurial bent like so many of us frequenting this site in particular) have so effectively been sold the illusion that class no longer exists that most have us have genuinely become blind to the idea that a company's interests (i.e. the interests of owners, shareholders, the board, investors, whatever - maximizing profits or ROI) and a worker's interests (e.g. a sustainable, stable and reliable income with potential for career advancement providing access to better pay/perks) usually run directly opposite to each other. Class conflict is inherent to the employer-employee or owner-worker dynamic. You can merely afford the luxury of pretending it doesn't exist when it's in their interest (i.e. doing so aligns with their goals, usually in the short-term) to "pamper" you - and that era may be drawing to a close within our lifetimes.
Every single worker is ultimately disposable. If you think your employer is disposable to you, that's not because you're special but because so far you've been extremely lucky. It is far easier for a company to replace a worker than it is for a worker to replace the company they work for - we just tend to see the "inability to find a new job" as a personal failure (i.e. bad performance at the job of "finding a job") whereas we take the existence of job vacancies for granted as a normal part of the market and maybe even a positive indicator for "growth" (which we define as desirable even if it's artificial or unsustainable).
It should also be pointed out that it's not just the money aspect. Managing people is difficult, managing people in a stressful situation is really difficult, add a dysfunctional culture (especially if that culture is "imposed" from above) is a pain in the proverbial. Which means managing in these situations is hard work.
Add on top of that that a largish number of managers just plain suck at their job, so being in a union can be useful to push back against either lazy or incompetent managers.
Because there are far more people who leave their manager than leave their job.
That if unionization is so cleary net positive for most workplaces, then it wouldn’t need any sustained agitation campaigns in the first place.
As any company that unionizes would near automatically gain a huge competitive advantage.