I mean, they tried something new. In some cases (RE4) it worked out really well. Its certainly better than just riding the ZOMBIES IN VIDEEYA GAEMS trend that was all the rage in the late 2000s to about right now (which would have been REAAAAALLY easy for Capcom to do if they wanted, since they were -THE- zombie game for a while.)
With better game hardware and better understanding on how to control characters in 3D space, suddenly the clumsy, slow zombies of the early Resident Evil games wouldn't have posed a challenge, since you weren't dealing with established camera angles that could (intentionally at times) obscure your vision, and clumsy tank controls that made moving, dodging, and aiming a challenge. The enemies you faced evolved with the full 3D rendered world spaces and better controls to continue to be a threat by being able to run quickly at you, hurl things, climb over obstacles, and have better AI about trying to flank you in groups rather than just all run towards a direct path line towards you, which wasn't what the T-Virus zombies were.
So they could have written some weird UHH VIRUS EVOLVED bullshit story, or try to take things in a different direction, which was creative and healthy, and got them to branch the series out from being just "The Zombie Game" in a growing sea of zombie games.
I'm not saying things always worked out for Resident Evil's attempts at growth. Some of the newer games are pretty damn bad, but I'd rather see failed experiments than safe, unoriginal carbon copy clones of one successful thing over and over and over, ala Call of Duty or whathave.
And ALL OF THAT being said, I'm pretty pumped about REmake 2: Electric Boogaloo. I played the original Resident Evil through rentals but the first one I owned (and therefore the first I played to completion) was RE2, so I'm ready to ride the nostalgia trip of my early teens, Capcom, good and ready.
And to all the nerds that think Claire and Leon's faces look dumb, they were always pretty, young, just turned 18 a week ago ladies (Leon was too), they were just a lot more anime in the old days. The change to something more humanistic with traits like a slightly imperfect nose or a butt chin rather than flat anime people with no imperfections is good.