Yeah, but that's still progress in a way, progress away from the false goal of unconditional realism. Cartoons are generally cheaper, which means we can have more things, and also has more useful design space. Something like TF2-style "all characters must have distinctive silhouettes" is much harder if you're also trying to do total realism, because you end up so much more constrained with where the distinctiveness can be. (Color? No, nobody's running around on the battlefield in bright red. Nobody's wearing crazy hats or has two-foot-tall bouncing hair. A lot of guns look a lot like other guns. etc.)

Things run faster when not realistic and are cheaper to produce (Normally)

I personally prefer the art style approach over trying to make it realistic/technical approach by making realistic representation as if it was real life. TF 2 > Crisis

This is a BIG why the Indie Game movemnet