I might be being too generous as I have a history of being optimistic about people's intentions and motives, but if she's actually autistic or just doesn't get a lot of attention normally from other vtubers, the forced thing could just be trying to get validation or even overcompensation in that sense that her first joke about the kiss didn't land so she autistically kept doubling down on it thinking that this time it'll be cool for sure.
Some people are just really bad in such situations and want to make sure they have some validation even if they have to force it. That or she was trying to clout chase, who knows.