I would be inclined to believe that if, based on what I have seen and what others have posted, there were any indication that Galchenyuk actually "hurt" the team enough to warrant him now being used as a 4th liner. I also don't think it's any stretch to claim Kuraly has been atrocious as a center. Who in their right mind would use Kuraly as a center over Galchenyuk? There's just no way. Charles Sarault is the center in Sarnia because he cannot play wing and he's actually a good center!
Galchenyuk didn't have his best game against Slovakia. Today's performance has nothing to do with anything because today's icetime wasn't based off of today's performance if you see what I mean (well, unless Gally made a huge mistake somewhere today that led to his line being used as the 4th) That still leaves his 3 previous games where I don't think anyone will claim Miller & co. where performing any better and thus deserved more icetime these last two games. In fact, in the first 3 games, Galchenyuk accomplished a lot more than any other forward on his team.
Calling Galchenyuk selfish is just completely unfair. Look at Yakupov trying to perform end-to-end rushes, look at Grimaldi trying to do the same. Galchenyuk has never acted as a puckhog. He didn't take any selfish penalties either. As for accepting roles, that's garbage: Galchenyuk made the team to be an offensive force, a key part of it, and everyone knows that. Now he's stuck playing with Kuraly, seeing his icetime reduced each subsequent game and hasn't done anything relative to his own teammates that would explain why he's in this position and not others - this last sentence is important.