I did _one_ virtual meetup. After the presentation we were paired into small breakout rooms. Two of the four guys in my room just gave a quick summary of their background and said they were looking for work -- they had nothing else to say.
(a) it ruined the networking time for everyone else and (b) if I had an opening, I'd be less likely to interview them than before.
i haven't been in this particular situation, but people who don't know what to say are all to common. i am not the most sociable guy myself, but i learned to get people talking by asking lots of question, searching for common interests, or simply anything interesting about them. it is a lot of work though, and after such conversations i tend to be exhausted. the irony is that if they didn't want to talk, but get me talking instead, all they would need is to ask a few open questions and then i'd be able to fill the space.
The other participant and I had a pleasant conversation, but the dynamic was weird for the other two who basically said "give me work" without saying anything else.