so I'm new to PS4 jail break scene but is it like switch where games need to be on a certain fw to play? I haven't seen much about this. So like if I backed up my copy of Spiderman would it be able to run on 5.05 or lower

No, since the game requires a higher firmware than 5.05
You can either:
A)Update, lose homebrew but play newer games right now
B)Don't update, keep homebrew but not play any newer games
C)Buy another PS4 and play newer games on there
D)Same as B but wait some time (Years) until a new exploit is available for higher firmwares

Yeah, on switch is not such a big issue because nintendo is shit at security, hackers already found an unpatchable (by software) exploit and they have more interested in cracking newer FW versions, unlike on PS4Ok so exactly how the switch is although you can bypass that limitation on the switch

By the time we're able to play Spider-man, Red Dead 2 etc... backups the PS5 will probably be here or close. I've already beaten those games anyway.
so I'm new to PS4 jail break scene but is it like switch where games need to be on a certain fw to play? I haven't seen much about this. So like if I backed up my copy of Spiderman would it be able to run on 5.05 or lower