Scott Cohen has 21 years of experience in the NFL and 5 with the Jets as assistant general manager. He started his career with the Redskins, working his way up from intern to a college scout. He moved onto Jacksonville, where he spent two seasons as Assistant Director of Pro Scouting. At that point, he went to the Eagles, where he was Director of Pro Personnel. He moved to the Jets and became one of Mike Tannenbaum's most trusted advisers.
The Jets' front office needs to be cleaned out from top to bottom. It's painfully obvious. The same people have largely been in place with varying roles and responsibilities since 2001. Hiring an internal candidate would likely keep many of the same people in place. The crew there has never built anything lasting. Whenever it looked like the Jets were close, they took a step back.
Beyond that, the front office has done a terrible job recently. You can say it might have been all Tannenbaum. That's unlikely. A general manager has too much on his plate to do it all himself. There are so many players to be looked at that most of the heavy lifting has to be delegated. The people in the front office formulate his decisions. Those people haven't been very good at anything. If you want to say there might be a few people who are good, perhaps you are right, but most people don't seem to be.
As for Cohen, I'll refer you to the Jets media guide. It says, "Cohen assists Mike Tannenbaum on the day-to-day operations of the team with a primary focus on player personnel. In addition to overseeing the pro personnel department, he prepares advance reports for the coaches, evaluates the top college players for the draft, and develops a plan for free agency." You name something significant the Jets have done. Cohen has most likely been involved.
What's the point of even firing Tannenbaum if you're going to hire Cohen? He would represent no change. This might be a courtesy interview. One can only hope and wonder what Cohen has done to merit such courtesy.
People who have followed the Jets for a long time generally convince themselves the Jets are going to make the dumbest possible move. That is because those who have followed this team for a long time have consistently seen this team make the dumbest possible move. That's what hiring Cohen would be. I cannot think of a credible argument for him to be general manager.