Personally i'm of the opinion that if you can point at a game and say "that looks like a XYZ game" where XYZ is some period-specific identification then that itself makes XYZ a visual style.
E.g. "that looks like a PS1 game" or "that looks like a 90s game" or "that looks like a DOS game". And that includes "that looks like a PS3/X360 game" too, even if it is probably too soon for many to accept that :-P
Huh, an interesting conclusion to me is that I'm another decade or so there will probably be nostalgic artwork recreating the HDR, brown, grimy vibes of late aughts action games
