I mean, if they’re smart, it’s an option on the table.
Current estimates for case fatality with COVID19 is 2.9%. It’s highly infectious. Put 15000 nerds in one place and then tell me which 3% should get sick and die.
Public health is all about large numbers, and that’s the kind of calculus you need to do to be responsible.
Of course, I also have biases. There’s no “right” move, there are just moves that square with your goals. Sure, you could try to hit 0 risk (although even the most risk-averse public health official will call that overkill), but then what kind of quality of life do you have? I could ensure the food supply is 100% safe by testing all of it - and then nobody has food to eat.
I will always put the onus on corporations and large structures in these cases, because again, public health is about large numbers. If you do a thing that attracts 15,000 attendees, sure you could say “eh but they didn’t have to attend,” but that’s a dick move that ignores reality. Of course nerds will abandon common sense to go to PAX - that’s the culture they’ve built, and PAX exploits that to make money.
But if you follow my logic everywhere you have no fun, and then what’s the point?
There’s no cut-and-dry answer, so ultimately I do not fault any entity for being overly cautious. I will only fault for insufficient caution among power-wielders, because they had a choice.