Actually no, I do not agree with that. I know there is always this idea among fans and media that skilled prospects should be played with skilled players, but I don't dig that. I don't think players should get any special treatment because they're a high pick or whatever. Should have to earn those opportunities like everyone else.
There's a lot of skilled player and a lot of skilled prospects on this team (or any team - this is the NHL), so why take a top six spot from a Connor Brown or Duclair, who are on their last chances to establish themselves in this league, or a Pageau or Tierney who are playing for contracts this year? I get that on the one hand, this is essentially what you're arguing for - that he should have to work his way into the lineup.
But there's a sort of developmental curve, where at a certain point, the amount that a player is developing playing top minutes at a lower level is less than what they'd get playing bottom six minutes at the higher level.
Now I'm not saying that's definitely the case with Brown, but he was almost a point per game player last year. Again, training camp and pre-season will decide things.
My main point is just, look at old Detroit, or currently San Jose, Boston, Washington, all these good teams that bring guys along slowly. Yes they tend to leave top prospects in the AHL for a while, but also, when a prospect gets to that point on the development curve where they're better suited to develop in the NHL, they have no issues starting top prospects on the third or fourth line and gradually bringing them along.