My current thinking is that BoC getting squatted, if there is even any truth to the rumour, will simply be a rebranding of them for AoS with a more trademarkable name (Gorherds of Chaos or similar). They'll then get a refresh of the Bestigors, Gors, Ungors and character models with more dynamic sculpts, and the old minis will be sold for TOW.
They aren't going to remove basic Beastmen from AoS, because the question then becomes "if there are no Gors, what are Slaangors and Tzaangors exactly?", and whilst it's possible they'll simply merge Goes into the other chaos books, at this stage in AoS's life that's going to ****** off a lot of people (there are people who have built BoC armies from scratch after AoS was released, purely for AoS, and telling them they no longer have an army is very different to telling someone with an old Fantasy army that they can't use it in AoS).
I do think it's fairly likely we'll see AoS BoC get more big monsters etc., probably with a few that don't overlap with TOW at all, as big monsters kinda fit AoS better than fantasy in the whole.
We'll see though. But I sincerely doubt GW will actually squat a while faction at this point. After all, the last time they squared a faction they're customers went on and on about it for thirty years until they brought them back 😄