Brady has never in his life put up high end numbers at any level, to expect him to start doing it in the NHL is setting yourself up for massive disappointment.
The guys people comparing Brady to like K. Tkachuk, Iginla, Benn, M. Tkachuk etc were elite producers at every level.
I'm not saying he can't get better. But he would need to improve his skating, balance, hands, shot, pass execution by a significant margin. Which he could, but its a lot to ask for.
Benn's production at the junior level wasn't insanely high though. This was his production in his draft year, D+1 and D+2 seasons:
D Year: BCHL 53 GP 42 G 23 A 65 PTS
D+1 Year: WHL 51 GP 33 G 32 A 65 PTS
D+2 Year: WHL 56 GP 46 G 36 A 82 PTS
Then in his D+2 season at the WJC he put up 6 GP 4 G 2 A 6 PTS
Given Tkachuk's production as the WJC, USNTDP/USHL and then his production in the NHL in his D+1 and D+2 season it doesn't seem like it would be that unreasonable to expect similar production to Benn if he had gone the CHL route those two seasons instead of playing in the NHL.
This then creates a real question about what was it about Benn specifically and his development that allowed him to have such high production at the NHL level 7 seasons after being drafted? Maybe it is an anomaly or there isn't a solid explanation behind it but it is worth thinking about. This then relates to Tkachuk, if Benn could achieve that peak 7 seasons after being drafted then what is it about Tkachuk or his development that prevents the possibility of such an outcome?
Zibanejad is another example of a player whose junior level production doesn't seem to predict what his NHL production has eventually become. There are lots of examples of players like this so it really opens up a lot of questions about what lead to that outcome. Can we understand these situations well enough to predict when it might happen again in the future? Is there something about their development process that can be emulated so that other players can achieve similar leaps in production? What are the relevant factors and how can we know when that can be achieved with certain players and when it can't?