PS5 Backwards Compatibility could already be in the works by the lead architect of the PS4

[Jason76]

Source: https://www.vgr.com/sony-has-filed-a-patent-for-backwards-compatibility/

With Mark Cerny working on this, I’m guessing that it’s going to at least be compatible with PS4, but I will be (pleasantly) surprised if it works with PS3 or older games.