It has nothing to do with points.
It has nothing to do with skills. Nylander has elite skill but below average vision for a first liner, very similar to Kadri. Kadri never was and never will be a first liner.
My qualification is that I watch the game not the puck. Do you watch the ball when you watch football? If so then you don't know how to watch football because you are supposed to watch the line. The line knows where the holes will be before the quarterback even gets ready to move the ball.
All sports that move quickly are the same.
Back to hockey, if you watch first liners when they are Nylanders age they are obviously first liners. McDavid and Eichel are the most recent and most obvious examples. The Leafs haven't had many lately.
Again, Nylander has top level skill but he can't keep pace with first line NHL speed. Maybe second line. If you don't see it you aren't watching properly. The only way that I can explain it is to not watch where the puck is but where it will be in the future and then watch for players that know where it will be. Nylander isn't one of them.
I know everyone is entitled to their own opininon, but... Wow.