I wouldn't mind it, if he had supplied suggested mitigations.

I think every one of those animations are system-supplied ones. Some are likely SwiftUI ones, which heavily abstract you from the iron, and, if other frameworks are supplied, the abstraction goes even farther.

It can be a major engineering effort, to improve a half-second animation.

That said, this is how designers work. I have worked with some of the top designers in the world, and it can be tempting to want to strangle them, as they choose a half-pixel alias as the hill to die on.

But if we try to work with them, it can make an enormous difference in how users react to our software.