Well, I never played TS3, so I can't make any comparisons with it, and maybe I'm just not noticing the blocky pizza because I don't care about it, but I guess, as usual, it all comes down to each player's individual priorities. As I said, I dislike TS3's graphics even though I've heard many fans call it "realistic".
TS2, as much as I loved it back then, seems extremely outdated to me when I compare it to 4. It had only four default hair, eye, and skin colours, only three body shapes of which the "fat" one was just slightly pudgy, a genetics system from Hell that made children born in-game look like the unholiest of abominations, same for randomly generated townies, I couldn't mix and match clothes as I saw fit, had to recreate rooms from scratch if I found that I had built them in the wrong place, and the worlds were big and empty. These may be mostly superficial things, but important to people like me who don't only play the game per se, but also use it to bring their novel characters and other fantasies to life.
I don't want to badmouth TS2 because as I said, I used to have a lot of fun with it, it was great for its time and a huge improvement over the first game. But TS4 is great in its own way, and I appreciate the improvements it brings to this life simulation. You may no longer be able to send your pets to work, but now your sims can actively work as veterinarians. The worlds may be smaller, but you can freely travel to any world at any time, meaning you don't need a fitness centre or a library in every single one of them. Vampires come in their own pack instead of being part of another pack, which may seem like a cash grab until you realise they're also much more elaborate than ever before; in TS2 they were basically just ordinary sims with a skin condition and strange eating habits. And so on...
Have you ever played TS4 yourself? I'm not asking this to challenge your opinion about the game, but because you said you're an administrator of a Sims Facebook group, which means you're probably still at least half a fan of the franchise in general, and that in turn gives me hope that my thread here doesn't have to stay dead forever...