No this won’t happen. They actually were thinking of switching to an algo called ProgPOW a few years back to get ASICs off the network and last minute it was cancelled. It was cancelled because the ASICs aren’t a 51% attack risk so they moved on.

If there are going to be issues with ETH going fully POS they will just revert to the old mining algo, I don’t think they will change it so ASICs get booted off the network.