Howard, regarded as an ascending player, became an unrestricted free agent. He will draw considerable interest on the open market, meaning there's a good chance he will sign elsewhere. That would be a blow to the Jets, who don't have a logical in-house replacement. Howard's backup last season was Oday Aboushi, a fifth-round pick who didn't dress for a single game.
The draft is deep at tackle, so the Jets probably could pick one with the 18th overall choice. But, with so many other needs, it would be counterproductive to address a position that could've been solved by locking up Howard on a long-term deal.