I put Jordan as a clear #1 over Lebron and here's why:
DETAIL.
Jordan was a late bloomer, who was cut from his high school team as a frosh or soph. He developed by growing and obviously had elite athleticism, but he had to work for his spot at 12. Jordan was an incredible student of the game and his attention to detail was Tim Duncanesque.
Lebron, on the other hand, was a huge elite basketball player at 12. He was already a guaranteed NBA player. Because of this, Lebron is not as focused on detail as he should be. That is not to say he doesn't have an elite feel for the game. He reminds me of Oscar Robertson that way. However, time and time again, he relies on his elite size and athleticism. Game 6 vs. the Spurs where Ray Allen hit his last second corner shot proves my point. Lebron makes a careless turnover as SA moves to close out ther series. Lebron cannot react in the moment to the first defender he's ever faced who can meet him athletically and is relentlessly ON HIM. He's still got size on Kawhi, but in the clutch, he commits two huge turnovers. Jordan committed key turnovers too, so that is not my point here. Rather, in the huddle with the Heat down 5, Spo draws up a play for Lebron to take a 3 at the top of the key, which is one of the most efficient 3 point shots (other than the corner), there is. But Lebron is distracted, distressed by his TOs, and he's half paying attention. This is NOT a mistake Jordan would make. The play rolls out and Lebron uses a pick to take his 3-pointer, but he IS NOT at the top of the key. He's three steps off to the side, significantly reducing his %. He bricks the shot. Badly, but fortunately the ricochet ends up with Bosh who throws it desperately to Lebron who hits the 2nd 3-pointer - a crazy difficult shot, btw. As an aside, after Lebron's 2nd horrific TO, he points at Bosh sheepishly, implying that it was Bosh's fault. It wasn't. It is also proof that in this moment, Lebron is falling apart a bit and is unfocused. It is also a weakness that Lebron has showed in huge moments from time to time: Failure is due to a teammate not doing something they were supposed to do. Usually Lebron atones for this mistake after the game by taking ownership, but I consider this another product of always being the best player in the gym since he was 12. You don't make mistakes, inferior teammates do.
Anywho - Jordan would never ever in a million years not hit his spot. Jordan would insist on getting to whatever spot he KNOWS he is most efficient shooting from, and most likely, he's been on the sidelines visualizing what he is about to do. I don't get the sense that Lebron plays that way.
Lebron is still the 2nd best player of all time, but I would love to see him finish out his career with an elite coach who would insist on attention to detail. I am looking at you Pop.
Until then, Jordan's attention to detail is why he is clearly the best of all time. Not the guy you want to be your top dog in the locker room and definitely not the guy you want to be stuck in a tent with for a week. That guy would be Lebron. But we are not having best teammate argument, but rather, best of all time.