What hilarity would ensue?

Awful! DMs need to be generous with their world and submerge their own personalities to let the players play.

Ah, a good answer. Thanks! I was being silly, but good point.

Think Biden would be any better? Senility doesn't make for a good DM.

Depends how good a storyteller he is. Lots of grandparents are.

Fair point. Although I think if most of the other players were pretty autonomous and they just needed a DM for bare bones guidelines and structures, they might be able to compensate.
Kind of like teenagers who are already semi autonomous being taken care of by an uncle or grandpa who may not have experience raising children, but these children are already almost adults so it shouldn't be too hard.