afconvert(1) lets you convert between various audio formats - most noteworthy is that it gives you access to Core Audio's superior AAC encoder without having to use iTunes/Music:
afconvert music.wav -o music_160kbps_aac.m4a -b 160000 -q 127 -s 2 -f m4af -d 'aac '
lipo(1) lets you operate (replace/extract/thin/etc) on executables and libraries to tailor their supported architectures: lipo <universal exe/dylib> -thin arm64e -output <new apple silicon-only exe/dylib>
replies(1):