Just because an album was released during a certain President's term doesn't mean the songs were written during that term. Obviously some songs were (e.g. Ronnie Talk to Russia), but I would argue that there are tons that were written before said term and kept in the vault until Prince wanted to use them. Plus, did any albums have delayed release dates?

PS. I'm willing to sacrifice good Prince albums for a Democratic President. The future of the world is more important in the grand scheme of things than a kickin' Prince album.