IIRC for GTA5 it was all satire aimed at mid 2000s Fox, both the trashy reality TV side of it and Fox News. I'm not gonna say it doesn't revel too much in the spectacle of just taking something that's already awful and dialing it up a bit, but it's more in the style of the Onion where most of the bits are taking the mask off an institution or trend and having it honestly portray itself as what it is (like the Fox News expy literally having the tagline "confirming your prejudices" or an American Idol expy literally just being assholes reveling in cruelty) than South Park style nihilism - it has a point to make and that's that American culture is reactionary and repulsively self-centered and consumerist, even as it is itself reveling in being trashy slop.

You've got to remember, everything after GTA3 was written in the context of the Bush era and none of it was written after gamergate: it has the sort of incoherent dirtbag quasi-left contemporary counter culture stance of recognizing the US as bloodthirsty, pointlessly cruel, and deeply unserious but also not having any sort of framework for understanding or addressing that and being entirely too libertine and chauvinist on top of that. It's kind of alien to anything we have now, because that whole counter culture basically got wiped out by gamergate crystalizing the chauvinist libertines into open fascists baying for blood and forcing everyone else to stop tacitly tolerating them.