Magnificent Seven’s Slowing Growth Threatens S&P 500 Rally

Last week, DeepSeek’s emergence as an AI threat wiped half a trillion dollars of value off Nvidia Corp. Last night, Alphabet Inc.’s disappointing earnings sparked questions about its capital expenditures and put its stock on pace for the worst drop in more than a year.

The jolts reflect a deeper concern about a key narrative that has underpinned much of Big Tech’s rally for more than two years, and thereby the US market’s strength: is all the AI spending going to pay off?