Maybe he is talking about this: https://coinmarketcap.com/charts/

Crypto marketcap went from 9b to 66b in just a year.  So we could be close to top of bubble. He is offcoure speculation since no one knows for sure.  Reality is that when bubble will pop few coins will not lose that much. The ones that bring nothing ofcourse will since they also gained for nothing. But this is also an speculation.