The Foundation Model point is real. As an iOS developer, what excites me most isn't the performance — it's what on-device inference does to the app architecture.

When you're not making network calls, you stop thinking in "loading states" and start thinking in "local state machines." The UX design space opens up completely. Interactions that felt too fast to justify a server round-trip are suddenly viable.

The backporting issue is painful though. I've been shipping features wrapped in #available(iOS 26, *) and the fallback UX is basically a different product. It forces you to essentially maintain two app experiences.

Still think this is the right direction — especially for junior devs just learning to ship. Fewer moving parts, less infrastructure to debug.