why does Kanye West always look like his jaw is wired shut?

It was for long enough. Doctors shouldn't have re-opened it!

Might be lockjaw. Maybe he does/did a lot of speed or other stimulants.

An astute observation. I'll add this to the board see if we can't get to the bottom of this.

There was an article on him not smiling. If you thought he was a tit before, now you will be left wtih zero doubt.

https://www.theguardian.com/fashion/2015/jan/27/-sp-kanye-west-on-the-real-reason-he-never-smiles-paparazzi
“Back when I was working on Yeezus,” he tells a reporter at High Snobiety, “I saw this book from the 1800s and it was velvet-covered with brass and everything. I looked at all these people’s photos, and they look so real, and their outfits were incredible, and they weren’t smiling. People, you know, the paparazzi, always come up to me: ‘Why you not smiling?’ And I think, not smiling makes me smile. When you see paintings in an old castle, people are not smiling because it just wouldn’t look as cool.”
he has been caught smiling