I remember a discussion with at least Shatner and Stewart, I believe it was The Captain's Summit, where Shatner admitted to Stewart that he had never watched a single TNG episode. They seemed to know each other pretty well and be personal friends, so the TNG actors that were present couldn't help to be mildly shattered (no pun intended) by that confession.
I'm not quite sure if it was ironic or meant as some sort of joke, since I don't know his personality (only some of his roles). Are there other statements that support the theory of his discontent of TNG? Am I reading too much into a joke?