I think that's a different question then if it's obvious.
I don't really understand the obvious claim. If it was obvious to investors and executives then what? They knowingly spent money they knew was a waste?
I wonder if for those who it was very obvious for "put their money where their mouths were" and bought a set of securities that would make them a ton of money on what was obvious when the obvious materializes in real life.
then, with that ton of money, they could buy enough shares to influence the board to implement their agenda.
in theory, this would quantify the definition of "obvious".
Bubbles don’t exist? I’m sorry, but to paraphrase an old quote, the market’s can remain irrational, longer than your faith in a rational market.