Everything you said needs to be judged based on the context. There is also a case of tallest tree grabbing all the sunlight and overshadowing other potential talent.

If you want to build a strong resilient team you should allow your devs to fail.

For your every valid example I can show you terrible choices people make in realworld because someone with a lot of experience told this was the perfect thing to do and they resisted changes.

Ofcourse you have to exercise sound judgement in everyday life. I have seen managers who are reluctant to hire rockstars simply because they don't need them.