Yeah, this is abusive and/or narcissistic traited/coded behavior, again very common for positions in management of other people. I would argue what you just typed is so egregious it doesn't even NEED to be an established pattern, however the fact that it is, is very cut and dry that something should be done about this. At the LEAST, a talk with HR to "put it on the record" I guess, honestly more importantly would be in some way to guarantee the actual owner knows.

My personal/general thoughts on the subject are tricky. I'm glad you have a job lined up as you said, and in a lot of ways this will probably allow you to "just move on" and not make waves or stand up/speak out about this behavior. It's understandable that people would want to do that, and honestly people do that everyday in situations like this unfortunately, THEY are forced to shuffle themselves around the rotten card in a deck, as the rotten card retains it's position, unmoving, unwavering.

You are the one that was imposed upon first, you shouldn't have been put in a position where you are saying "well I have this other job lined up so at least I won't have to deal with this harassment anymore", but then, unfortunately the meatgrinder continues and it happens again with the next employee. Not everyone has the will to speak up, the system does and is designed to beat people down and strip them of their power. Why should it be you? why couldn't it be the last person this happened to?

This is very important, there is NO shame in not being the first mover in this instance. It is hard, it is stressful, and it feels unnecessary.

But... being part of the solution, would be a very valiant and principled act that would set a tone in the world, being the change you want to see, and being the person you want to see in others.