It might just be because I'm color sensitive and consider pure yellow to slightly orange-tinted yellow my favorite color.
This is about my ideal spectrum (maybe a bit more into the orange spectrum, but you get the idea).
This is the (approximate) base color of the more saturated Pac-Man:
(#FFDD00)
This is the (approximate) base color of the less saturated Pac-Man:
(#FDD95D)
See the difference? The first one is in the spectrum of my favorite colors, and the second isn't even close. That might be what puts me off on the second one so much.
I still do prefer the more simple World design overall, but I actually kind of like the more saturated GA design as well.