I've met Brent Spiner on a couple of occasions out in public, away from conventions and stuff. While I honestly can't say he was rude or abrasive, I got the impression that it was an imposition for him to deal with being recognized. One time he let me take his picture, but was emphatic that I don't put it online. I respected his wishes, but come on! I'm just a Trek fan. Let me put this on Facebook to show off a bit.
Unhappy with his character? I can't say. But it strikes me that if so many of his latest roles seem to be appearing as himself, t he ol' career may have hit a few snags.