History Says Investors Should Listen to Warren Buffett: The S&P 500 Is on the Verge of Doing Something for the First Time in 155 Years as Investors Buy "Nothing But Hope."

This is less a sell signal than a warning that the marginal buyer is now paying for perfection. In that setup, the market’s leadership becomes fragile: any earnings miss, higher real yields, or softer buyback activity can trigger disproportionate multiple compression in long-duration names before fundamentals actually roll over.

The most exposed names are the ones whose valuation is most dependent on future growth staying uninterrupted — NVDA, NFLX, and to a lesser extent GOOGL — while AAPL is relatively better buffered by cash generation and repurchases. BRK.B is the cleanest beneficiary of the regime shift because its cash hoard becomes more valuable as a volatility buffer and as dry powder if a de-rating creates forced selling in higher-beta equities.

The contrarian point is that frothy valuations can persist far longer than skeptics expect, so the immediate trade is not a blind equity short. The higher-probability path is a time-structured correction: flat-to-up prices over days/weeks, then weaker relative performance over 1-3 months if rates stay sticky or breadth narrows, and a more meaningful reset only if earnings revisions turn down. What would falsify the cautionary thesis is continued upward EPS revision breadth plus falling long-end yields; that combination can keep CAPE elevated without imminent air pockets.