I somehow managed to get a masters degree from the top engineering school in my country (with honors), and get hired at MS and Google, and a handful of other places, but that was in spite of my interview performance, not because of it. I've also failed a lot of interviews. I literally look and sound like an idiot when adrenalin kicks in, which for me it does at the most inopportune moments.

I very strongly suspect that there are _a lot_ of people who suffer from this. You can recognize them when they on the one hand have an illustrious resume and on the other suck pretty bad on simple coding problems. Those things are supposed to be mutually exclusive, and they usually are, except when the person's blood is full of adrenalin and they end up on the wrong end of fight-or-flight response.

If I spent 7 years as a SWE on high profile teams at Google it's pretty clear I know how to code, even if my interview performance on your Leetcode problem is not excellent. My C++ and systems design will likely be way better than all of your existing engineers, in a non-interview context, just because I've done a ton of both in an environment which expects excellence in both, and won't let you commit code if it sucks. 5 years after leaving I have not worked anywhere where this wasn't the case.

This is not the same, BTW, as "high pressure" usually encountered in the work environment. I can deal with that just fine. And I can code whatever algorithm you like in that environment, no problem. So I doubt a high pressure interview is terribly predictive of performance under "normal" levels of stress, too.