Why have the big seven tech companies been hit by AI boom doubts?

Primarily, there is concern about whether the vast investment in AI byMicrosoft, Google and others will pay off. This has been bubbling away in recent months. Analysts at Goldman Sachs published a note in June with the title "Gen AI: too much spend, too little benefit?" The Wall Street bank asked if a 1tn investment in AI over the next few years will "ever pay off", while an analysis by Sequoia Capital, an early investor in ChatGPT developer OpenAI, estimated that tech companies will need to earn 600bn to pay back their AI investments. Zino says the Magnificent Seven has been hit by these concerns.