I agree. I actually went to see a taping for two shows at NBC studios in NYC. He balanced the panel nicely and pretty much slammed everybody. He also didn't have any of those vile snarky and disgusting comments like he has now.
But, over time, I think he figured out that it's easier to make it in the entertainment biz if you just bash conservatives and adopt all of the old, tired liberal positions.
He moved the show and himself to LA, where diversity of opinion is not allowed. Instead of fighting or merely submitting lamely to the thought police in the entertainment/stripper industry out there, he decided to become commandant of them.
He's just a surly unfunny vicious bitter animal now.
I remember one episode where Kathy Ireland was getting attacked for being pro-life. One the liberals came out and claimed that a fetus wasn't really a human being. Maher interjected and asked "Well, what is it then? A frog?"
Originally, he came off as a straight-shooter who enjoyed being a smart-aleck and poking holes in peoples' arguments. It made for a lively show because he gave no one any mercy and was just as hard on a self-important liberal as he was on a humorless conservative.
But you're right- to stay popular with the "in-crowd" in LA, you can't stray too far from standard orthodoxy, unless you're a really big star.