I agree a lot with your statements that Ruby used to push boundaries more and that it became too conservative (while hiding behind empty statements like "it's good that it's boring).
But on the other hand, we have features like Guilds/Ractors, that promised solving most pressing issues with GIL and concurrency, but their implementation is half-baked at best, they are slow, not reliable, don't work with Rails (the latter might not be language's fault, but still).
I can kind of understand why people are not very trigger-happy to try out new things in their production code, given the bad history of releasing new things with Ruby in past few years. And this is the only way to wide adoption. Libraries can't do it, because they usually target older versions of the language as well.