I mean, the gondolas are free-hanging in the air as they move via the cables. And if you were to be in a small box, trapped without any means of escape for over 90 to 120 minutes; how would you react as the gondolas's swing from the wind?
Also, this isn't exactly as if the system was constructed and tested for a short period: this thing's been testing and cycling for months, and they didn't account for an issue like what happened tonight to occur (I do think part of this is both on Doppelmayr and Disney, for a few reasons).