Shipping LLVM bitcode is mandatory for the AppStore, Apple can then compile that bitcode to binaries for different hardware.
That's why if you are shipping code to the AppStore, you probably don't really care whether Apple uses x86, ARM, RiscV, powerpc, or all of them in different devices. Producing working binaries becomes Apple's job.
(You do not ship binaries to the AppStore, but LLVM-bitcode, that Apple compiles for you for whatever hardware they decide to ship next).
If you are not shipping Apps through the AppStore, you are on your own.