I agree. His answer about whether the Users are still there– that definitely sounded pessimistic. Same with his prediction that Flynn probably wouldn’t survive his first match.
And the way he reacts to hearing that Ram died, that really looks to me like the response of someone who’s used pessimism as a not-really-healthy coping mechanism for a long time (if you always expect the worst, it can’t hurt you quite as much when it happens).
He’s capable of joy, but it takes a lot to bring it out. I think it’s partly mirroring Alan, and partly being written as a security program– his job is to look for bad things happening, so he can stop them.
(In 82 he’s very confident in himself, in his ability to do his job. He’s just not confident that any of the things out of his control will ever turn out okay.)