I'm just going to stop you right here and counter with this equally true statement: Any and all credibility goes out the window when you (the general you, not the specific you) argue that any player is definitively a top-6 lock coming off his age 18, age 19 or age 20 season merely because of some uber-spectacular stat line in a lesser league, especially in their age 20 season like Neighbours had.
Of course, if you want to talk about his D+3 year or whatever, I'd like to bring up Kostin. And Schmaltz. And Ty Rattie. And Brett Sonne. And others, who had great after-draft seasons and sucked ass in the NHL because they lacked basic skills to stick in the NHL. You know, like Neighbours lacks - which might include, but certainly isn't limited to: a good shot, consistently good passing, defensive awareness (as evidenced by his drifting around the defensive zone constantly looking for the breakout pass, when he's not just standing up high in the zone like he bought a prime seat to watch the game), creativity that is more than one go-to move in the offensive zone, and the ability to do useful things off the rush in the offensive zone besides stand in front of the net on occasion. Hell, I'd even question his general skating, because he has the ability to skate and use speed, he simply lacks the desire to do it more than perhaps twice a game and prefers to drift around or do the toe-push thing like he's saving energy for a 4th OT 3 nights from now.
But I'm sure 2-3 more years in the NHL will change all that and he'll become a well-rounded player capable of playing that top-6 role I've heard he can fill since the night he was drafted. Or, he'll go the way of the guys mentioned above. I'll (heavily) bet the latter.