It depends where you draw the line of "enough to get by". There are two cases: case A is where the expectations exceed what you're really being paid for, i.e. those cases you mention where the company culture is long hours. This isn't what I'm on about, but for completeness, these places are awful to work at and I definitely agree escaping them is the most rational thing to do.

Case B is different. Case B is where you work somewhere with reasonable work-life balance, but where you have a colleague who persistently under-performs. They won't do the essential documentation, follow the process correctly and they will quite happily sit through meetings and not volunteer a solution they know the answer to unless explicitly asked in just the right way and they happen to feel like it that day. This can take a few different forms - my list is not exclusive but it boils down to "quiet quitting" - but, as you say we are all adults, and we know who these people are.