Yes, there's no way to win as the hiring entity, you just open yourself up to discrimination lawsuits. So it's better to do the inhuman thing and say nothing!

That's right. The other reason to not give feedback is the rejectee will inevitably start arguing with you about it, demand more detail, try to reopen negotiations, tell you how unfair/wrong you are, etc.

I've tried it both ways. Not giving feedback works much, much better.

Yes so if you’re gonna ask this question ask over phone not email! I’ve successfully gotten feedback by doing this. Not in super detail but very good general feedback.