I'm currently trying to go through the three Fromsoft "Souls" games that I haven't played, so I'm starting with Sekiro. I finally got my hands on a PS5, so now I can play the Demon's Souls rerelease. That just leaves Bloodbourne. I'm willing to wait for a year to see news of a Bloodborne release for PS5. If not, then I'm just gonna buy a PS4 off ebay or something and play it there.
You can just download Bloodborne on the PS5. It's backward compatible. No need to purchase a PS4 for it.