That's exactly what has happened with Nvidia. Over the past year, Nvidia stock is up by 166% as the surge in AI investment has been a massive tailwind to the business. On the other hand, even including its massive dividend yield, the YieldMax NVDA Option Income Strategy ETF is up by about 105%. That's 61 percentage points of underperformance.

The high-flying AI chip superstar seemed to run out of gas in the fiscal 2025 second-quarter earnings report it released on Aug. 28. While the company beat estimates on the top and bottom lines, the differences were narrower than investors were used to, and guidance was also less impressive than some had hoped.

There's no question that artificial intelligence (AI) stocks have led the charge in the current bull market, but in recent months, that leadership seems to be fading. Some investors even see a potential AI bubble emerging as valuations have arguably gotten ahead of business growth.

Nearly every day for the past few months, Huang has sold Nvidia stock. For example, on Sept. 12 and 13, he sold about 200,000 shares, worth more than $20 million.