"AAPI" is truly the epitome of a DEI term that is racist in exactly the way the ideology pretends not to be.

Really, you're going to group indigenous New Zealanders with Han Chinese as "one" racial group? Just to pick two very different groups at random. There are many absurd pairings that fit under "AAPI" and it's a parody of itself.

It's erasing these cultures to group them all under one constructed postmodern umbrella

A more pragmatic reason for this approach is many subgroups lack sufficient population sizes in relevant candidate pools to realistically attempt such a high-context focus with any sort of evaluation of efficacy.