i might be wrong but sated devourer not lowering alpha strikes cooldown was a conscious decision
master yi just got a "bug fix" to make sated devourer lower the cooldown of his q, but i distinctly remember a red saying that they purposefully made it not lower his q's cooldown because they didnt want master yi to be using his q every second
with this change master yi is going to be kassadin tier until he gets changed back