The facts you point out are one reason I do expect a huge drop back down at some point. Overvalued, liquidity driven markets have a nasty habit of going higher than most expect on the upide and lower than the newly optimistic crowd thinks after the ride ends.
“The things that will destroy us are: politics without principle; pleasure without conscience; wealth without work; knowledge without character; business without morality; science without humanity; and worship without sacrifice.” Mahatma Gandhi