Most GMs do, you made it sound like they don't at all. Your point to, once again, was make the NHL look bad in some way. The NHL still has the best players in the world.
What you're saying is nothing but a straw man. Did I say that the NHL doesn't have the best players? No. Did I say that NHL should let their players play in the WJC? No. That's just you putting words into my mouth. I have no problem with teams not letting the best prospects like Barkov and MacKinnon play in the WJC. The Panthers pay Barkov's salary, not the Finnish Ice Hockey Federation.
I think there are very few GMs in the NHL who would let guys like Crosby, Stamkos or Patrick Kane go to the WJC. It's only natural, and I have no problem with it. Letting a guy like Rasmus Ristolainen go to the tournament is a different deal completely.