David Trainer is making what he calls his "boldest call ever" that the AI bubble "is about to pop" due to liquidity squeezes. New market dynamics from increased inflation and Treasury yields are key components backing David' bear case. He adds that IPO valuations in companies like Anthropic, OpenAI, and SpaceX (SPCX) don't make sense when examining balance sheets and puts more pressure on public companies to outperform in the coming earnings season.