Declarative frameworks are deceptively simple. The promise is that "anyone can use it" - be it UIKit experts or entirely green developers. However, as this article makes clear, a deeper understanding is required to make SwiftUI views performant.

It's too easy to end up with accidental anti-patterns scattered throughout your views.

Plus, there are more ways to accomplish a given design now. Developers are left to figure out everything on their own without realizing there's a very specific intended approach.