Mine is that the useState hook is an actual plague on the entire React ecosystem. Regardless of your opinions of React, if you wanna use something then use it right.
Nah, no language is "perfect" once you've used it enough I write python for money and elixir in my own time. I borrow implementation approaches from functional when it's appropriate. Avoid using complex classes, especially if the encapsulate state. But they have their uses and people should chose which works best for their use case
I wouldn't write cli tools in elixir for example.