The behavior often indicates they are not very balanced in general and are over expressing themselves kinda like a coping mechanism. If they realize that it is happening, they are probably quite uncomfortable with it too.

I didn't have issues with stuff like this before I was disabled. After spending most of the last 10 years in near total isolation, I have a hard time shutting up any time anyone is willing to talk with me IRL. The worst part is that I'm usually trying my best to mask my level of pain and I go down hill fast. By the end of an average casual conversation I'm down to half the wit needed to end the conversation gracefully, and my graceful half has already left.

After watching how people dealt with covid isolation, I think I have handled it pretty well. Now I have a lot more empathy for people dealing with this kind of social anxiety. It's still annoying as hell, even when I am the one doing it, but understanding the condition helps blunt my angst.