Although interestingly, Android development on the other hand was actually hampered for a long time by the slow emulator

If your doing Android Development with the ARM emulator, then its crazy slow. However, if you use the x86 emulator - then you get native speed.

Xcode/iOS's emulator is actually x86 - which is why it seems faster than Android's default emulator.

Xcode doesn’t emulate anything, it runs the entire iOS userspace as native processes on top of the macOS kernel.

It "emulates" the hardware - e.g. you can inject shake / GPS / etc

This is the same as the Android x86 "emulator".

IIRC the Android uses hardware-assisted virtualization through Intel HAXM. iOS simulator is run entirely in userspace in a seperate launchd context.

(Mostly referring to the actual processor/OS itself; buttons that "vibrate" the phone are not really technically interesting to me.)

The annoying part about the default x86 emulator that installs from Android Studio is that it's incompatible with hyper-v. Requiring a reboot to disable.