What smart people are saying about what IBM's AI warning says about SaaSpocalypse fears

CEO Arvind Krishna wrote a letter to shareholders eight days before the company was supposed to release its quarterly earnings. Mandel NGAN / AFP via Getty Images IBM's CEO released a letter to shareholders on Tuesday to warn about a "performance shortfall." The revenue miss renewed fears about a SaaSpocalypse. We gathered what business and tech leaders are saying about the letter — and its wider impact. IBM is on pace to have its worst day ever on the stock market after saying it misread the…