In practice I've found that web standards are mostly driven by people who are willing to spend the time and effort to iron our all the edge cases.
I've had a very pleasant experience contributing to things like `fetch` and negative experiences contributing to some other things - essentially it's a "people problem" more than a technology problem.
I find the pleasantness of the standards process depends on how many people have strong opinions about the thing you're working on. Being involved in 'new' standards like fetch or gamepad or webgl is generally pretty relaxed because while it's interesting to many people, there aren't a bunch of people with Past Experience with the new api/standard and they aren't about to dedicate a bunch of time to doing it themselves.
Coming in to try and fix problems or propose improvements for existing stuff like canvas or XHR or whatever is another matter entirely, as you've probably noticed. Thanks for helping make fetch good!
I've had a very pleasant experience contributing to things like `fetch` and negative experiences contributing to some other things - essentially it's a "people problem" more than a technology problem.