You’re over thinking it. Like all top tech companies, they just want the best engineers.
Ah yes, Palantir is "just" a tech company.
Notwithstanding the fact that tech companies hire dogshit employees all the time and the vast majority of employees of any company of size 1000+ are average at best, Palantir happens to be rating so high on the scale of evil that I'd pop champagne if it got nuked tomorrow.
If any company would do it, it would be Palantir.
On the contrary, they hire the trendiest: https://danluu.com/programmer-moneyball/