Is that so? I see a lot of people not wanting to switch for solely more money because they expect to hate it at a potential new company.

Yes and the same works for founders. If they expect, they will hate it after buyout, they will probably resist.

But what if new opportunity is ok, gets you 30% more money, but your departure makes your current company very sad and perhaps worse place for everyone to work at?

I wouldn't expect a lot of support for the idea of staying if you ask the internet for an opinion.

The two aren't unrelated. In the distant past companies had professional and personal development programs. Some even had a commitment to try to avoid layoffs.

When MBA culture took over in the 80s it became normal for companies to act like extraction machines. Employee loyalty crashed, with a corresponding increase in churn.

Taking investment money makes it hard to create a humane culture. But smaller private companies do at least have the option to consider it.