I guess if your shipping to TestFlight you still have the feedback loop, but it seems like it's adding a lot of steps. Whereas, if you were working on a app in a desktop environment, just build and boot to the simulator right there.

I could see the use case for the planning stage of the build though if your out and about and have a good idea.

If you could actually build and test locally I think I would have different thoughts. For instance, if I'm building a utility script for the CLI and can run it locally it makes sense not to whipout the desktop in some scenarios.

I used the simulator for a while when I was first building, but now that I'm building software that syncs in realtime between the watch and the phone, I found the simulator isn't enough - and sideloading doesn't consistently work with the watch! Testflight is another 30 seconds per build.