In the last decade, we've had many learning experiences around governance of programming languages. Most of the changing languages that come to mind, I realize, that they, too, had a big upset or oops related to governance. I now think one of the key things to look for in a programming language is governance -- what they say about how they do it, what they actually do, how that's working out so far, and how you think…
While I agree this is an important problem, I don't think there is a satisfactory answer. Programming language evolution is more or less a complexity management, while you also have to balance requirements from various stakeholders. Almost all governance drama came from one group of stakeholders complaining about requirements essential for other group of stakeholders, and you can't always satisfy both. (Rust `async`…
For example, if a language designer and implementor says upfront that they want to run it as Benevolent Dictator For Life, and also that they don't want to see feature PRs from people, because they prefer to work through all the details themself... That's their right, and great information to have upfront. That governance might tentatively work for some adopters, and others will decide it's a showstopper without needing to explore further.