Just because he is Rick Nash, he should be able to break the rules like this without punishment?
Yes, it's right to let players get away with abusing officials.
The biggest reason the IIHF has clearly dropped the ball on this issue, is because of the increasing amount of officials, especially at the minor hockey level (and even in different sports), being physically abused by players, fans, parents, coaches, and anybody who wishes to get their hands on a ref who has somehow pissed somebody off with his judgment during a hockey game.
There is a reason why state after state (or province after province) is making laws against physically abusing sports officials. That's right, in an increasing number of places, people will go to jail if they touch a game official with any ill intention. I'm not saying that Rick Nash's actions are worthy of such legal punishment. However, if things like this get very wrongly labelled as accidental and at a high level like the World Championships, little Rick Nash fans on skates will think it is alright for them to go after a referee if they don't like a call. If you don't believe me, pay attention to some sports officiating websites, and see the near-daily news stories about the latest sports official who has been attacked. As a referee myself, the increasing trend has me a bit worried, especially at elite levels where I admit I wouldn't last too long in a tilt with some of the players.