There were no real parameters in the OP other than NFL TE.
We must be talking about one of two scenarios. Either he chose football over basketball from the start, i.e., after his junior year of high school, or he chose basketball and decided to try football at some later date, similar to Jordan and baseball (and Deion and baseball, and Bo and football). I realize there was no reason for him to ever consider either scenario given the advantages of being an elite NBA player, as many have articulated in this thread, but that is the hypothetical under discussion, so I will set that aside.
In the first case, I assume:
- He would have played football as a high school senior.
- He would have gone to an elite program like Ohio State or Notre Dame.
- He would have trained for football instead of basketball. Perhaps that means a bit more bulk, assuming he was slotted as a TE. It also means his football specific skills would have improved, he would know how to block, run TE routes, etc.
- Given his combination of athleticism and skills described throughout this thread, he would have excelled in college football and been a highly drafted TE.
- He would have excelled as an NFL TE. He would have been similar to Gronk and Gates in the challenge of how to cover him and as a red zone threat.
The only thing that would have derailed that IMO would have been serious injuries, and there is no way to project that. As has been pointed out in the thread, he has been amazingly durable in the NBA, but the NFL is also more punishing on the body.
In the second case, I assume he would have tried to make the transition in his athletic prime. The ESPN article linked earlier was written in 2010, and someone in that article said he would start to play well midway through his first season and would be a top player by season 3. That sounds about right to me, again assuming no major injuries to derail him.
Of course, in both scenarios, it would matter what team he went to, their style of offense, the level of QB play, etc. For example, if he went to New England (Brady) or San Diego (Rivers), he would have been much better off than if he went to the Jets or Dolphins.
Having said all that, I voted Good to Excellent.