I agree with you, just my obsevations from using SwiftUI "in anger" for the last few years, performance is atrocious on macOS and acceptable on iOS, especially with some tuning.
Oh yes, I agree, it's not as bad on iOS for sure.
But acceptable for a premium device is a very low bar to clear.
It becomes much less acceptable over the years as well, infuriating.
In my country the mainline iPhone start around 1k€ and even the "e" is over 700€.
If I had paid 2-300€ like a low-end android device I would find it acceptable but Apple only sells stuff that is the high end of pricing, therefore it is not acceptable.
