It's also a dumb strategy because the good people will easily find another job and leave and you end up with office full of the least competent employees.

But yes I'm pretty sure this is a big part of the reason for these mandates.

From what I've seen (at a fortune 100 company) they made the supposedly "best" employees fully remote, and they neglected to tell the others that there were "limited slots" for fully remote and thus they had to come in to work. After a few months of coming in for work, they then laid off those employees, as not enough people quit for that to happen. To be fair, I was given a severance, but it still sucks. And the office was in bad shape, bathrooms poorly maintained, cafeteria in disarray, with substandard food (compared to before). The reason they're trying to get rid of employees is to make their stocks look good. We did better during covid by all measures, when everyone was working remotely.