If swearing at the beach is unacceptable, full stop, then it's unacceptable for a person with or without TS. (Personally, that sounds like a dumb law, but what do I know)
A TS individual for instance may be annoying, however they aren't causing actual physical harm to other people, in the same sense that a murderer might be.
But I do agree with the idea that letting someone off the hook for all consequences on account of a mental illness isn't viable. That makes things a lot harder for neurodivergent individuals, but that's why we should have extensive support programs and provide resources to help them cope with the expectations of general society.
It's a tricky problem, because to meaningfully distinguish between someone who is mentally incapable of following a law and someone who is capable of doing so but systematically elects not to, you are functionally deciding which humans do and do not have free will on an individual basis. I think most people would believe that either all humans have free will, or no humans have free will, not somewhere in between, so this is a scenario that is uncomfortable to pretty much everyone.