Two points:
First, Tatum and Brown are not at the same place as far as leadership goes. It seems pretty obvious to me that Brown is a leader and Tatum is just Tatum. It wasn't just the 20 points in the first quarter, it was the manic intensity on defense and the conscious attempt to bring along other teammates. Brown made sure to get good looks for Tatum and Thompson even as he was clearly taking over the game, and to Tatum's credit, he made a couple of great passes back.
Tatum and Brown play like separate islands, and it is not a good trend. It was nice to see the first quarter play out differently. There was some slippage after that by Tatum where he went back to his old habits, but it's something to build on.
Second, Walker and Smart are not leaders, and it isn't because they've missed games. Walker is a genuinely positive guy and Smart is super competitive, but they display no other forms of leadership. They don't adjust their games to what the team needs. They don't course correct in games when the team stagnates. They don't sense when they need to get another player going. They just do what they do.