It's not clear to me why they booed him. you think for only asserting predictions that benefit him? Not because they agree on those predictions and don't want that future, blame him for this role in it?
My guess is because of what he's done, or at least perceived to have done, in the area of AI. Because what he said (at least to me) didn't seem boo-worthy, but in the context of who is saying it, I can see it.
Put another way, if someone that the audience liked said the same things, its not clear the person would get booed.
These ghouls live in a totally different world than the rest of us and actually think everyone shares their positive outlook on AI.
We need more of this booing. Put up a consistent front and let these people know their views are not shared.