Ask yourself, why are "web standards" or "standards bodies" good? Why should they have "power"? The W3C held back the web platforms for years.
What's the point of having an extremely complex standard that nobody else will ever implement anyway? Remember, it would take billions of dollars to implement a competitive browser and then you have to give it away for free.
If even a trillion dollar company like Microsoft thinks it's better to team up with a competitor rather than implement HTML all by themselves, it really should make you think.
Consider, there's only one Linux kernel, there's no "Linux standard", just one kernel - and the world runs on it. I don't see people running around complaining about how that's a threat, even though it's much harder to switch operating systems than browsers. Sure, there's POSIX, but that's a tiny subset of Linux features.
I wouldn't call POSIX a tiny subset of Linux features. POSIX makes up the vast majority of the kernel interfaces that applications actually use. Stuff like epoll and io_uring are the exception, not the rule.
Standards bodies are powerless if there's only one implementation.