What if Palpatine in TRoS is just a personification of the dark side, and not Palpatine himself? It takes the corporeal form of Palpatine just because of the galaxy’s shared trauma of this one dude.
Yeah, that’s a pretty obvious way to get rid of Palpatine surviving, and one I recall being discussed in the past. Shouldn’t be too hard with lines like “All the Sith live in me” or whatever it was.