Why do you think Jeffery Gundlach is wrong when he just said literally everything is overvalued? Everyone knew it was a bubble in 2001 and in 1929, that's part of being a bubble, it doesn't make sense but it just keeps going up ignoring all risks. Is there liquidity for a little more yeah maybe, but when everyone is long and highly leveraged there is only one way for things eventually to go.
I do know who he is, why do you assume I don't, just so you think you can appear smart on the internet? Pretty pathetic. Gundalach has better investing success than you and Fama, you should listen to what he says instead of just assume he's wrong, that's called being intellectually dishonest.
Why do you think he is right? Lots of people detected previous bubbles. The problem is that the same people also missed or called out bubbles that never happened.