Ironic: I think the idea is to indicate how open you feel at that moment to being social. I get how doing that without actually socializing seems ironic, but I can also see how this would help avoid social interactions going needlessly bad because one participant just wasn't in the right mood.
I have strong doubts about people keeping this up to date, however. I could see it being used as a kind of S.O.S. by someone who needs some support, but doesn't want to impose on others who might not be up for providing it.
You're absolutely right about the lack of integration into other platforms that actually facilitate that socialization, however.

Isn't teletherapy the same? It can work IF done right (and, yes - that's a BIG "if").