I run a “Hacker News advocate” against the comments I post, and this was one of the things I thought of. You will note that in that case Sony actually suffered quite a bit in their response, and they only really did it out of fears of piracy. In this case the I believe backlash will be fairly large, not the least from their own platform security people for having years of their work invalidated. Also, in this case the only thing I can see that could drive them to do this would be if FairPlay keys were somehow made available in the fully unsigned OS environment: I haven’t really looked into this (don’t have my M1 Mac yet) but I would be very surprised if so.