Mark Zuckerberg has promised this is the "year of efficiency" – out is the metaverse, in are cost cuts, focus, discipline. But one noted tech investor says it's about more than just righting the cost structure of the business and cutting some payroll – it's about repositioning the company to take advantage of the next great wave of computing. Couldn't do this and not mention A.I. once. Can Zuckerberg turn around this ship, and what his relationship with Wall Street can tell us.