Uh... as an American/Canadian dualie I can state that this simply isn't the case. The reports of timeliness are mostly tied to super rich folks that would get treatment faster in the states because they'd cut in line in front of people who need that treatment more. Up here healthcare is prioritized based on need.
The clause about barring excessive health costs isn't unreasonable, Canada, as a country, is basically an insurer and is being dickish about letting people with pre-existing conditions onto their insurance who haven't paid into it, this is a defense against the US's broken system that would encourage all sick citizens to flee to Canada. That said when I immigrated I had several long term health issues that posed no barrier to entry and the cases where this is enforced are rather rare.
Canadian healthcare is perfectly fine, but it isn't your rebound date when the US healthcare fails you. People shouldn't immigrate just to take advantage of the system.
All that said, I am hopeful you guys will get Medicare for all down there and actually cut your costs-per-patient and enable people to be more free to pursue their individual liberties.