I fully understand the logic in play here. Been on enough flights out of ORD during the winter where pilots just don’t give a fuck. If you go back to the gate, you will be grounded and nobody is leaving. If you stay on the tarmac “waiting” for as long as possible, there are good odds you get to take off. Pilots want to get out of the airport just as much as passengers do.
There need to be stronger safety regulations to prevent this from happening. But it is very easy to imagine a situation where the pilots didn’t realize how bad it was getting in the cabin and figured “We’ll be given the green light to taxi to a runway any second now”