Bringing back Palpatine in order to allow Ben Solo to recapitulate Vader’s sacrifice from ROTJ in order to once again kill the very same being would make the ST feel pointless. It would seem that ROTJ’s ending was broken down to be kicked a couple movies down the road and then redone.
If they have to bring Palpatine back, I hope it’s a vision or something rather than a true post-mortem consciousness. If Lucas had any say in it, I doubt that’s what would happen.