I wasn’t just talking about using a cleaner style of speaking either. Choosing topics and the depth of these topics is part of communication as well. Those should be picked according to prior cues (the community you’re in, previous exchanged comments etc.)
I think everybody should “dumb themselves down” on social media. Since you can only assume other people’s background on a given topic and their grasp of (for example) English, you should write in a way that’s understandable to as many people as possible while still getting your point across. That’s just how good communication works.
If it was one of my coworkers I would offer them to come to me if they either need someone to talk to or need a distraction. For example going on a walk during our break or go get some food together, though these may not be applicable to your workplace.