You also can't just leave out the bond market.The dotcom bubble sat on top of the 10 year bond at 5%. The US had a balanced budget and 10X less debt than now. It was the peak of the unipolar moment. Part of the AI bubble is the lack of safe investments to act as a flight to safety. I just don't think they are really comparable. The AI bubble could certainly be more destructive given the circumstances and concentration when it pops, even if not bigger. The other main difference is we actually had the internet in place. So much of what is fueling the AI bubble doesn't even exist.