I think it is because using Apple is not mandatory. Apple is an aspirational brand, you use their products because you want to. Microsoft's products are not; they pushed hard their product everywhere, and were difficult to avoid, if you wanted something else. That itself caused a much friction, and when they start to steer you somewhere you don't want to go, their products are not exactly going to be your favorites.
This is a desktop OS. You're comparing Windows 11 not letting users select which browser they'd prefer on a PC OS to iOS, which is a phone OS. A more apt comparison would obviously be to compare Windows 11 and macOS. macOS doesn't force you to use Safari, lets you specify which browser you'd like as a default, and respects that decision, only bothering you about it on major updates. Even then, only bothering you with a popup that asks if you'd like to try it.