The Philadelphia 76ers lost Guerschon Yabusele to the Knicks, with New York signing the former Sixers’ big man to a two-year, $12 million contract that the Sixers could have been able to match with their taxpayer mid-level exception. Was it a mistake for the Sixers to let the big man walk to the rival Knicks as they wait on a decision from Quentin Grimes?