here come the over-reactions..... 
trade brown for pennies on the dollar because we didn't make the finals!! make our team worse because brown was bad in a series!! because tatum and a bunch of lesser players is much better...... thats ensuring you never will make the finals again...
Brown has improved every year and if you have a player like that who is young you keep them. and let them grow. he's still not yet in his prime. does he have warts? yes. but trading him because you lost a playoff series is just massive overreaction.
don't be the Oklahoma city thunder who dismantled westbrook/KD/Harden.
Trading Brown for pennies on the dollar would obviously be a mistake, but I don't think anybody is recommending that. If we're being honest, this team pretty much has a floor of 2nd round playoff team for the next decade with Tatum and anybody you surround him with. We are lucky to be in the situation we are in.
I agree that we shouldn't just trade Brown - he is a deserving All-NBA player who has improved every year he has been in this league - but it's also possible that someone else might better complement Tatum. I also think we have him for at least one more season anyway. He would be foolish to decline a supermax extension and it would be difficult to trade him this offseason unless he chooses his destination (but then you are limited in what assets you get back).
I don't know about that.
This is one of the most talented supporting casts in the league. We have three phenomenal (role player / supporting cast wise) guards in Smart, D White and Brogdon. We have two excellent bigs in Horford and Rob Williams. We have high quality deep bench pieces in Hauser, Pritchard, Muscala. This is about as talented a team as we can hope to have around Tatum & Jaylen.
I was thinking the other day that if you removed Tatum and Jaylen from the squad and replaced them with average forwards (decent starter level players), this team would still be a slightly above .500 basketball. A 44-46 win type team.
This is a really talented basketball team.
So back to the original point, if they are only this good with a phenomenal spporting cast around Tatum & Jaylen, how good would they be with an average supporting cast? How good would they be with a below average supporting cast?
An average supporting cast might get them to the 2nd round fairly consistently. I don't think a below average supporting cast does. And this is with both Tatum & Jaylen.
Take away Jaylen. Just Tatum. Can they realistically expect Tatum to drag a team to the 2nd round year in year out? Regardless of the supporting cast, or with little regard to who is in the supporting cast? Tatum hasn't shown that. Only guys like LeBron have shown that capacity. Even great players like Dirk and Kobe struggled to do that. Both MVP talents. LeBron a possible (likely) top 5 All-Time player did that. Can we really expect Tatum to? I don't think so.
We need to give him a strong supporting cast (if no Jaylen) to realistically expect regular appearances in the 2nd round (or beyond).