I believe it was a design choice, to make the characters feel unique rather than just make them look like some rando/anonymous S.W.A.T. team.
That's what Hunk and co. did, and did you care about any of them? I sure as Hell didn't.
Yup there was nothing distinguishing about them, the only think is HUNK was the only survivor,
Mr.Death. So i agree with your initial response about the
STARS uniforms to make each character feel more unique. I never really questioned it too much, and also wouldn't have it any other way.
Also i wanted to point out a couple of changes i have noticed. Firstly HUNK shows back up in RE4 Mercenaries with a slightly alternate looking attire/gear. It just has a few things that look clearly and distinctively different from his OG RE2 appearance. One particular thing is on his mask the eye pieces are red. AND now anytime we see HUNK in a game they always just reuse that RE4 Mercenaries character model. I don't know if that's
lazy, but check it in
Mercenaries 4D, Operation Raccoon City, Revelations, RE2R...
That's prolly also why in ORC they made all those Russian Umbrella characters,
DELTA Team i think with Lupo, Vector, and the rest of the gang each look very different.