Today's massive AI company valuations are based on market sentiment ("vibes") and debt-fueled speculation, not fundamentals, just like the 1999 internet bubble. The market will likely crash when confidence breaks, long before AI's full potential is realized, wiping out many companies but creating immense wealth for those holding the survivors.

Warren Buffett's market indicator, comparing total stock market valuation to GDP, is now over 200%. This far exceeds the 150% peak during the dot-com bubble, suggesting the entire market is in historically overvalued territory. This amplifies the systemic risk of a potential AI-led correction.

During the bubble, a lack of profits was paradoxically an advantage for tech stocks. It removed traditional valuation metrics like P/E ratios that would have anchored prices to reality. This "valuation vacuum" allowed investors' imaginations and narratives to drive stock prices to speculative heights.

Historically, small-cap companies grew earnings faster than large-caps, earning a valuation premium. Since the pandemic, this has flipped. Large-caps have seen astronomical earnings growth while small-caps have lagged, creating a rare valuation discount and a potential mean reversion opportunity for investors.

Cliff Asness differentiates two market manias: 2020 saw wider value spreads (pure valuation extremity). However, the dot-com bubble was uniquely dangerous because investors paid massive premiums for low-quality, "crap" companies—a toxic, multi-dimensional combination of risk factors.

History shows that markets with a CAPE ratio above 30 combined with high-yield credit spreads below 3% precede periods of poor returns. This rare and dangerous combination was previously seen in 2000, 2007, and 2019, suggesting extreme caution is warranted for U.S. equities.

While media often highlights the costs of being public, the valuation multiple is an overlooked benefit. A consistently growing small business can command a 20x P/E ratio, far exceeding the typical 3x cash flow multiple offered in a private equity buyout.

The dominance of passive investing (~65% of the market) and the decline of sell-side research have created a structural inefficiency in small-cap stocks ($500M-$2B). With fewer active managers doing the work, valuations in this segment are extremely attractive, creating significant opportunities for diligent investors.

The current environment shares key traits with 1999: a narrow, AI-driven market and extreme valuation gaps between large-growth and small/mid-cap value. This parallel, combined with a backdrop of economic acceleration, suggests a period of significant outperformance for SMID value stocks may be ahead.