I know that remakes and remasters are contentious, but let's pretend whatever game in question you're thinking of is handled with the utmost care by your favourite devs and they absolutely nail it.
Mine would be Shadow of Memories (called Shadow of Destiny in North America). It's legitimately one of my favourite games of all time but it kinda flew under the radar and I haven't met many people who know of it let alone played it. Seeing it get modern graphics, maybe some expanded mechanics, would be soooo cool.
I had the same thought initially, and unfortunately it wasn't just GTA. However, IMHO Diablo II Resurrected was an amazing exception, and I'm sure there are others. Plus, the OP's question was probably about an ideal case and they wanted to know what people have been missing from the past.
Realistically, I wouldn't expect a decent comeback of Guitar Hero 3 for example, but it sucks that it doesn't really work on Win10/11 anymore, and while Clone Hero exists, it doesn't have the same "story" mode as GH3 had, with characters, milestones and such. Hell, you can't even get "booed out".
Too bad that as you mentioned, even if there was demand, a random big company would just buy the rights, do some lazy upscale and sell it like it was gourmet shit.