That's so interesting to me, because I've personally found online play slows things down to a crawl. Maybe if my online groups were composed of more tech savvy folks, it would be different, but between technical problems, people talking over each other and needing to repeat, and needing to flip between various windows/screens/apps (let alone how much more prep time things require) and making sure everyone is seeing the same thing at the right time, I've always gotten through more material as both player and DM in person.