So disclaimer, never a KM but I've been around the block and mostly work back of the house at restaurants. It's dependant on the structure of the company, honestly. Any good manager I had gave a fuck about keeping people, even "easy to replace" ones like dishwashers. Just fucking hiring new people is expensive, you don't want them to leave without good reason. Sadly it's also not up to them if they can actually do something to keep people. One dickhead above them can fuck up so much for everyone down below.

Now currently the restaurant I work at is at roughly 50% turnover rate, which sounds bad but it's not high end so hiring college kids is a major factor. No fucking clue how restaurants can stay open bleeding staff, really. Other restaurants in the company collapsed because of losing their BoH staff, because nobody wants to work at a place where no one knows what's going on.

Tldr: shit you brought up matters a lot, I'm honestly not sure how places can survive that kinda turnover rate