Of all the games to trouble updating a console for it is Battlefield 2042? I haven't been this confused since someone wanted to play elf bowling on the DS.
Anyway I don't know what has been done on the PS5 thus far as far as blocking updates but retaining online, most online efforts require current firmware regardless of what the base game uses and PS5 hacking is way early on too. Just here more to say Battlefield 2042 is the thing that sees you want to update or risk things?