It’s a good thing when people leave for a place that suits them better. I would leave a team that made issues I don’t care about an important part of the job, but that doesn’t mean I think they’re doing anything wrong.
Telling employees there are other places they can go that are less hostile is still not a justification for having a hostile workplace. If everyone thought that way, nobody would ever tackle these problems. It's a mistake to try and equate this with some other technical choice, this is not the same as quitting a team because the boss wants to use C++ and you want to use Java.
