As a sidebar, when I started porting Xogot to Mac, my first reaction was "SwiftUI is just not up to the task, it is too slow".

I decide to give Instruments a shot with the new SwiftUI instrument, and was able to track down the problems - it took a while (and Claude scanning my traces), but Xogot powered by the same SwiftUI code from iPad on AppKit is smooth as butter.

It was just not as noticeable on iPad, as the touch interface would distract from the slowdowns.

I have this bad habit in SwiftUI, where instead of using new Views for components, I have many properties that share state:

struct Foo: View {
@State var someSharedState
var title: some View { ... }
var buttons: some View { ... }
var body: some View {
HStack {. buttons title }
}

Turns out that SwiftUI uses the "View" as the boundary of change, so if anything on my model changed, it would have to re-evaluate the whole view, not just say, the title.

Split your views.