PS5 Backwards Compatibility: Can You Play PS3, PS2, and PS1 Games on PlayStation 5? | Push Square
PS2 Backwards Compatibility On The PS4 Might Not Involve Discs | Ubergizmo
Sony enabled PS2 backwards compatibility for the PS4 without telling anyone" : r/PS4
PlayStation 5 backwards compatibility for PS1, PS2, and PS3 games could be provided by a revamped PS Now service with upscaling capabilities - NotebookCheck.net News
Hackers Just Made The PS4 Compatible With PS2 Games - YouTube