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.

That person is not even an academic. At least google Eugene Fama so you don't embarrass yourself like this.

What does Ja Rule think about bubbles? Ask him why markets can remain irrational longer than you can remain solvent.