Why? Played it to death when it was new, tired of LA from GTA 5 as well, time to move on to something NEW, not rehash the old. Don't give a crap about seeing CJ and friends in higher res, it's still the same OLD crap.
I'd welcome any kind of single player content, but R* doesn't do that anymore. Heck I'm just peeking in here after being gone for years. No GTA single player content, no reason come back.