When Nvidia crossed the $2 trillion market cap threshold on Friday, tech bull Dan Ives of Wedbush Securities predicted the party was just starting for artificial intelligence stocks. By the look of it, billionaire Marc Rowan is happy to be on the opposite side of that trade after his investment firm, Apollo Global Management, warned valuations have surpassed the excesses of the dotcom era. “The top 10 companies in the S&P 500 today are more overvalued than the top 10 companies were during the te...