David Brevik released that just after the Diablo postmortem from GDC a couple years ago: https://www.youtube.com/watch?v=VscdPA6sUkc

Worth watching for any fans of the original and if you want more context around that pitch. Lots of interesting tidbits about the origins of Diablo and Blizzard North.

And an amusing moment during the Q&A: Someone in the audience went up and gave David some money to make up for pirating the game when he was a kid.