This sounds like a cop out and a way to ignore the real issue. Imbalance in sport. How can sport be equal under a cap structure that tax varies from state to state?
It sounds like you support a sport that is not on a level playing field. I find that troubling. Why even call it a sport? It's entertainment not a sport and you must also the feel that Canada not winning a cup in decades is OK. There is nothing suspicious even though it's statistically impossible to happen on a level playing field.
Bottom line. NHL HAS MAJOR ISSUES WITH FAIR PLAY AND BALANCE.
Don't get me wrong, the tax structure is a problem... but your suggestion that "governments should fix this" is somewhere between completely ridiculous and completely unrealistic.
As for why a Canadian team can't seem to win a cup, there's quite a few reasons (beyond taxes) that are for the most part, unchangable.
1. Weather, in most of Canada, sucks during hockey season. The last truly cold-weather team to win a cup was the Blackhawks 10 years ago. Even Denver, isn't all that bad these days.
2. Hockey players tend to be pretty humble, under the radar, type of people. The best ones don't want to be the centre of attention. They don't want to get recognized walking down the street or grabbing a coffee.
3. Young hockey players in on Canadian teams get lauded as the 2nd coming, and don't neccessarily have to "earn their stripes"... look at the post-ELC contracts handed out to the Maple Leafs trio, even Elias Pettersson in Vancouver. To win a cup, you need a lot to line-up right, and that includes getting guys on bridge deals to outperform.
4. Getting into the "micro-details"... possibly because of the fan pressure, only the Oilers and Leafs have really been able to "bottom out" over a number of years to be able to get the pieces that you need to win. Edmonton has the 2nd worst weather in the league, and Toronto grossly mismanaged the contracts of those 3, along with running into some bad luck with respect to COVID.
NMCs, buyout penalties, that's all level playing field already. Allowing "Free" buyouts is what would create a imbalanced playing field.