I wouldn't compare a single prospect to Barkov. He had all the skill and obvious size when young with a bit heavy skating as his issue. He later on fixed that.
But the thing is, his arsenal is one of the broadest in the league if not the broadest. Skill, size, responsibility, and most of all he plays a winning type of hockey. Not only to showcase his own skill and greatness. Therefor I wouldn't compare prospects to him because that's not fair to expect. His game is so well rounded, effective, calculated and skillfully impressive. You can't expect that from most if any youngster.
Just to make it clear how good and important Barkovs roles in teams are? Finland could absolutely upset and win a best-on-best tournament. But some factors would be needed, and one of them would be a performing Barkov. He would be the most important factor with a goalies performance. Followed by Heiskanen and then Rantanen. And then followed by a overall sound and good two-way team game. He's more important than McDavid for Canada or any american for their team. And he is that for a upset contender. That should say a lot about his abilities.