I doubt this. Everyone has dreams or long-term things they enjoy working on. And UBI wouldn't be enough for most people, so they'd at least pursue some form of cash-generating work.
> 60% of the folks I meet would be pretty content watching TV all day, every day. When you talk to them, they just talk about the shows they watched.
My hunch is that many people would indeed find something other than mindless TV if they weren't having their intellectual/emotional energy used up on a daily basis by a job. Not all people, maybe not even most, but many.
What they got up to instead is a whole nother question, but I do really think that the typical human would find something active to do, given no forced use of their time.
Personally, I hang out with regular "normies" as much, if not more, as with technical people, and all the boring TV-watching "normies" I know do have dreams and hobbies, but it takes getting to know them better to discover that. And those dreams and hobbies are generally blocked by dayjobs and errands.
How many people would ignore education, socialization, and general societal cohesiveness if they knew that they would never have to worry about getting along with anyone else in order to survive.
First, crimes usually come with financial consequences I doubt that this would change even with UBI.
Secondly, its just as likely that the opposite becomes true and people learn to appreciate a sense of community much more deeply due to the lessening of competition. For instance intramural sports teams might become even more popular than they are now which could increase the general sense of camaraderie.
edit: grammar
I think that without constant competition it is equally possible that people would have higher regard for community than less. There are many things to consider here, but I am generally not concerned about people becoming more problematic or dangerous as a result of UBI.