A step back from the past 3d games as a whole. The games used to emphasize exploration and freedom more so than relationships. This is entirely absent in IV since the missions are mostly scripted, lacking in variety and creativity. There is nothing creative like Expresso 2 Go or Sayonara Salvatore in GTAIV. These missions in III completely allowed the player 100% freedom with no tutorial or hand holding, and stomps the shit out of every mission in IV. In fact, IV's best missions are the more simple missions like the one where you date the gay guy from Love Meet. Those are the wacky, zany, creative missions you'd see in a ps2 gen GTA. Stuff like that rarely pops up in GTAIV.
It's hardly rose tinted, I just have an understanding of what ps2 GTA's did best and what GTAIV has entirely abandoned.