I don’t think corporate AI needs to be very robust for the unnecessariat to be a thing. Black people stopped being useful to white people in the south when slavery was abolished, and even today they’re mostly being used to fill prisons and keep whitey scared. Native Americans have filled this niche since they were “discovered” by whites. Chinese workers became surplus once their railroad labor was no longer required.
This is a very old pattern. White people have been giving tacit permission for their corporations (and governments, and churches) to do this, for as long as the’s institutuons have existed. The only new twist on this, is now that it’s white people being shoved aside, we suddenly need a fancy name to explain what’s happening.