PS5 Backwards Compatibility: Can You Play PS4 Games on PlayStation 5? - Push Square
PS5 Won't Be Backwards Compatible With PS3, PS2, or PS1 Games - IGN
PS5 Backwards Compatibility Limited to PS4 Games
PS5 Console Backwards Compatibility for PS1, PS2, PS3, PS4 confirmed by Ubisoft? - Daily Star
Recently there's an influx of “PS5 backwards compatible” articles on google reporting it will play ps1 through ps4 titles. If it's true, much respect to Sony. : r/PS3
PS5 Won't Be Backwards Compatible With PS3, PS2, or PS1 Games - IGN
PS5 backwards compatibility: Ubisoft says PS3, PS2 or PS1 are not supported