I generally don't mind Dreamworks films, and I think the biggest problem I have is that they find a successful film, and they have to make a franchise out of it. Take Shrek, the first film was great, it was funny. But then they decided to make sequel after sequel, and each movie got less and less funny. It's the same with Madagascar, the first one was funny, the sequel just wasn't.
That doesn't mean the movies can't be good. Take a look at the Looney Tunes/Merrie Melodies, they are generally seen as some of the most important pieces of film, and yet they made plenty of topical jokes that have since badly dated, and they took plenty of jabs at competitors like Disney. And yet nobody criticizes them the way they do Dreamworks, instead the cartoons are highly praised.
I do realize there is a difference between 7-minute short cartoons and full-length animated features, and the WB shorts may have made their topical jokes more clever, but it is a bit hypocritical.