It's also a huge waste of instruction encoding space! Especially given that 99% of non-branch instructions just put 1110 (AL) or can't be conditional at all (1111).

Incidentally, available register read ports are the reason why cmov takes 2 µop on Intel architectures, but only 1 on AMD, since Intel's µops can only read from two sources but cmov has 3 sources.

Then A32 could have up 4 sources with a conditional op + register shifted register source.