Legendary hedge fund manager Paul Tudor Jones told CNBC that the U.S. stock market faces its "most negative flow picture" since 2002 in 2027. He attributes this to increased equity supply from upcoming big tech IPOs in the AI space, such as Anthropic and OpenAI, along with a recently completed SpaceX offering. Jones also expects more secondary offerings from companies to fund AI buildout, reversing the previous tailwind from corporate buybacks and M&A that decreased equity supply during the four-year bull market.