One thing about older animation is that it is hard to watch for long periods of time, because it was almost always shot on "two's" instead of "one's" like modern animation. In other words, each drawing was shot twice, lasting 1/12 of a second, instead of modern feature animation, where each drawing is shot once, lasting 1/24 of a second. While the motion is smooth, it's slightly less-smooth, and can be hard on the eyes after a while. The technique works for short cartoons, but is very difficult to watch for a feature duration.
That may also be another reason for a dislike of short cartoons, in that modern cartoons tend to be longer, with more plotline, instead of being a short premise for 7 minutes of gags.
Me, I'd say I'm pretty much in the middle. I probably prefer the new stuff like Superman, Batman, etc, but I also enjoy Fleischer's Superman shorts, and stuff like the Flintstones and the Jetsons.