I'm going to echo what some people are saying here: just because someone's mentally handicapped doesn't mean they're free from judgment, but it does mean that you have to consider exactly how they're handicapped in your judgment. If they're acting like they do just because they aren't understanding that it's bothering people instead of malicious intent I'd say your grounds for disliking him are a fair bit slimmer.
Honestly it's a really hard thing to say. There's certain things you'll judge socially inept people for that it's not considered acceptable to judge mentally handicapped people for. Things like the jokes that you mentioned. Regardless of what disorders they have some people will just tell really bad jokes and not get that they aren't funny. That's usually considered a perfectly acceptable reason to dislike someone for provided there isn't some sort of medical reason for it, even if the problem resulting in the bad jokes is the same.
I'd say that it's perfectly acceptable to be annoyed with someone like the guy you're talking about or even dislike them provided that you're keeping the reasons they might have for it in mind. So really just how you should treat everyone else
Honestly it's a really hard thing to say. There's certain things you'll judge socially inept people for that it's not considered acceptable to judge mentally handicapped people for. Things like the jokes that you mentioned. Regardless of what disorders they have some people will just tell really bad jokes and not get that they aren't funny. That's usually considered a perfectly acceptable reason to dislike someone for provided there isn't some sort of medical reason for it, even if the problem resulting in the bad jokes is the same.
I'd say that it's perfectly acceptable to be annoyed with someone like the guy you're talking about or even dislike them provided that you're keeping the reasons they might have for it in mind. So really just how you should treat everyone else