There are a lot of factors that go into layoff calculations, and often it isn't performance. In fact it can perversely be the opposite. Finished your project early? You're not doing anything now so you're expendable, bye! Or maybe you got into one too many heated arguments with your boss because you knew you were right and he was wrong.
And if you are bought by a PE it is often some guys spreadsheet that does the cutting. And many times that spreadsheet is total BS and used just because it seemed to work that one time they used it before.
I don't think that's a safe presumption, especially in the case of mass layoffs. Often every team will have to shed people, so if a whole team is made up of high performers they'll still have to get rid of good people. Then you've got the cost cutting nature of laying people off, sometimes the highest paid will be the ones with a target on their back.
The high performers are often on duties that have them directing the future of the company, things like planning to upgrade/rewrite that old legacy system. When it comes to layoffs they'll be let go while poorer performers maintaining the old system will be kept because they're needed for immediate operations.
Companies will layoff anyone not involved with "keeping the light's on", that doesn't correlate with individual performance.