Auston is a very unique player. He had to overcome an injury a year ago and finish that season as one of the top player in the US develop program, breaking Kane's record and would have been picked # 3 in a very deep 2015 draft if he was born a few days ago. He also had a back injury which kept him out for 3 weeks and only returned to play Pro for a few games before the WJC this year. He clearly carry the US team on his back for the first few games up to the quarter-final and may have been burn out because of that (not being on top of his game shape because of the missed time due to the recent injury and carry his team almost entirely by himself (with some steady smart grinding work from one of his line-mates). Remember that Fin gold medal team had a lot of talented players who were playing on top of their games, not just the two top elite 2016 prospects.
Funny things can happen at the WJC as well. McDavid was not the best player for team Canada last WJC either, but he clearly is the most overall talented player on that team and likely in the young NHL. Some of those production/result does involve luck and who you play with. Coming to this tournament, Matthew had hardly played with any of his teammates in the international tournament and a lot of the play was trial and error to find their chemistry.
I believe he is a real competitive player but he does not crave for the spotlight for himself. He already said that his favorite player is Toews and he would like to play like him so you know that he will step up when the big time arrive but care less about his individual stat. Who would not have loved to have a Toews on their team?
Not saying I would not like the two big talented forwards from Finland especially Laine, but if I am a GM and have to make a choice, I will go with Auston because he come from a city where hardly anyone even heard about hockey and he wanted to be a hockey player and did everything he could from an young age to get to where he is today. He loves this game and he is that determined.
While I agree that the success in the WJC doesn't alone indicate where a player is at in terms of development, though it shouldn't be sidelined either. Perhpas the Finns had the chance to create more chemistry than Matthews and Tkachuk, but they don't play in the same league team either.
I don't know the details of the Matthew's injury, did he break a leg or something? Laine f.ex. missed the whole summer off season workout due to a serious knee injury which lead to disappointing 2014-15 season. The next year when he had the chance to pick it up, well, you can pretty much see the results right now. Had he been healthy, one could only wonder how good of a skater he would be today.
I find the last statement to support the claim that a player should be picked first a little bit odd. Loving the game and being born in a place that most haven't even heard of aren't exactly factors that dictate the order. Puljujärvi was born in Sweden (Älvkarleby) f.ex. and it's a never heard place for me atleast. Then moved on to Tornio which is a never heard place for people that don't know the country. I'm fairly sure all the top picks love the game and there's no doubt Laine, Tkachuk or Puljujärvi are just as driven and determined as Matthews.
Being a center is a valid and good point for someone to go ahead of another (especially #1) if they are close in terms of skill, potential ability and NHL readyness.