Vaccinated is the key part of the title.
I don't like that as much as the next person, but if I'm visiting a hospital or a nursing home anytime soon, i'll mask up.
If a celebrity many different people per week, 20% vulnerability is still a lot. Its better than no protection, but still put the person at a pretty high risk.
Parties like the above can be problematic in a time of an pandemic even if one disregard covid. Any illness that can spread has the risk of causing additional stress on the health care system. I know for example some sport activities which has decided to reduce activity on the ground that the sport has the potential of accidents which would then put unnecessary pressure on an already heavily pressured health care system.