If you go back to the 1950's and include the days when Gordie Howe was in his prime, then ……… But that would totally miss the point, wouldn't it.
I get the impression that what you are doing is trying use slight of hand to give the impression that Canada is still dominant, when in fact the point is that dominance is clearly shifting away from Canada. Brent Sutter, who was coach of a dominant 2005 WJC team which formed the basis for Canada's OG Gold Medals in 2010 and 2014, said so explicitly after the 2014 WJC, where Canada finished in 4th place for the second consecutive year. He said (I can't quote exactly) that the world of junior hockey changed dramatically in the decade since 2005. It is even more so now.
You could make the argument that what is keeping Canada in the mix is that 70% of WJC games are played on Canadian soil or on the Canadian border, where Canadian fans will deluge and dominate the arenas. The increasingly dominant teams from Finland, Sweden, and Russia must overcome the disadvantages that come with crossing the ocean and playing 6,000 miles away from the time zones that they are accustomed to, and with all the other disadvantages that visiting teams have. It should be noted that, since 2010, when 3 of 10 WJC's were held on the European continent, Canada finished 4th or worse in every tournament. Home Sweet Home is keeping Canada in the running!