Actually, I think he's a bit mistaken in his analysis. First, back in 1999, most people followed the market by watching CNBC. Even though Internet was available, unless you were a day trader like me, you got your information mainly through old skool outlets.
He also states that everyone was euphoric and talked about stocks back then but that is not the case now. What he seems to conveniently forget is that, in 1999, the main channel of communication was through word of mouth. But who the hell does that now? It's all done through social media now. Does he not look at Twitter/X or other popular platforms? It's a never-ending buzz awash with people talking about Nvidea and Bitcoin. You can't say that ain't no hysteria.
Personally, I think the market hysteria now is worst than the one in 1999. Back then it was just sheer greed. Now, it has morphed into some cult-ish voodoo state of mind. We live in some really strange times.