Palpatine needed to be brought back. By bringing him back this ties the entire Skywalker saga together and gives IX a sense of true finality; he also needed to be related to Rey, to reinforce her toxic core belief that she is worthless. It also pays off RotS, in which he was set up to have a power to keep himself alive in a way Plagueis couldn’t.

I agree that Palpatine needed to be brought back for basically the reasons Abrams said in the quote you linked to. Star Wars isn’t the story of Anakin, it’s the story of Palpatine and those who fought against him. Not having him would make the Sequels feel like some unnecessary epilogue rather than a natural continuation.

That said, Rey being his granddaughter is dumb.