Before I go on, this subject reminds me of a Funny or Die video:
http://www.funnyordie.com/videos/8063d74c6c/idiots-with-zoe-saldana-kate-bosworthThe video suggests that beautiful people are just plain idiots, or perhaps that plain "smart" people feel threatened by them and perceive them to be idiots.
I'd go along with the notion that some of Liz's unfair reviews came from people who were jealous of her good looks. I think it does come into play. But there's a lot to otherwise consider:
1) Liz's unpolitically correct "Fuck You" shtick also rubs some people the wrong way, even though it is obvious that Liz isn't trying to hurt anyone. The "system" is fucked up and Liz is always there to point it out.
2) Liz does flaunt her beauty. For example, look at this week's background of lizphair.com. Or look at a number of photos from her numerous albums.
If you want to have your head spin, think for a second that Liz is aware of all of this.
On the flip side, Liz has turned down Playboy, probably numerous times.
At the end of the day, you can really only judge Liz's music by tuning everything else out and just listening to it. Most of the people on this forum have figured that out.
Now, go watch the video again. And laugh.