Of all the things you could critique DSA on, this is the hill you're going to die on? 
DSA deciding to do a mask mandate at this event is unequivocally good and based. Shut the fuck up, you fucking dipshits.
Imagine being this much of a fucking goddamn crybaby about masking. Eat shit, you ableist fucks.
One of the biggest lessons this pandemic has taught me is the astounding number of people for whom leftism is really just performative, and that when push comes to shove, these people will make the biggest fucking stink about having to do something even mildly inconvenient for even a single fucking event or context and show themselves for who they really are.
I mean I don't want it to be the norm forever, at least not outside of big events where it makes sense, but with covid still going around in waves....
Plus, the way to not have to wear masks in the future is to actually wear them when there is a pandemic and actually tamp down on that shit
At this point I believe it's just cognitive dissonance, everyone said it was time to stop masking, and repeated a bunch of thought terminating simple explanations as to why, and the mandates all dropped, so it was normalized. Accepting that they should still mask at conventions now has implications for what they should do day to day, at the store, and what they should have done over the past year or two, so they reject the new thing instead of doing some self refelection