I think it's pretty even. I still see Brown as Jimmy Butler with a three point shot and Tatum as a skinny Paul Pierce. I think they can meet those expectations. Nothing this year has made me change my mind about that.
I think Tatum, in trying to expand his total game, expanded his game in ways this system isn't a good fit for. This is not a "give it to the guy and everyone else go to the other side of the court and let that guy do his thing" type of system. But he is intelligent and I think he will figure it out and take a big step forward next year or the year after.
Brown on the other hand appears to have worked on things that have enhanced his game in this system. And, except for a bad 20 game stretch to start the year, Brown has had nothing but a developmental curve that is increasing every year. He was better last year than the year before and right now, he is playing better than he did last year. He just keeps getting better.
And I think there is a lot of recency bias here. People think the better player is whoever happens to be playing better at that time, so yeah, in the first 20 games people where loving Tatum and hating Brown. Now because Brown is playing so well and Tatum isn't, people have changed their mind.
I think they are both future All-Stars.