Yes tech companies get sued for discrimination in hiring on a routine basis. The issue with giving feedback is the you hand evidence to the opposing side in a future lawsuit. There's very little benefit for the company, and a lot of risk.

Microsoft settled three years ago on a race discrimination in hiring thing. And two years ago for discriminating against non-citizens (and in some twist, Facebook settled the same year for discriminating against citizens, so... damned either way).

Just this year Workday got sued for discrimination in hiring, which is mildly hilarious because they're the HR-as-a-service company.

> Or is it just the amorphous possibility of suits?

It's mostly this, driven by the lawyers. They've seen a few previous settlements and just decide "well, none of that here".

I don't know if you've ever done hiring at a big company, or sat through the legal training things, but even if you don't draw a lawyer who tells it to you straight, it's pretty easy to infer what's going on.