But a 1991 7% national goods and services tax fixed it all pretty much single handedly
...
You're going to have to define what you mean by "fixed it all" here. Because if I'm not mistaken, the Canada debt to GDP (with the 7% "VAT") is very similar to the USA debt to GDP (without a VAT).

Not as far as I can tell.

You get different figures using gross and net debt, and also depending on whether you include state/provincial debt, but the usual summaries are fairly compelling:
icaew.com - Chart of the week the debt of g7 nations

Canada's central government net-debt-to-GDP at around 37%, and its current year deficit as % of GDP, are both the lowest in the G7. I think Germany pulls ahead if you use gross debt to GDP.
And Canada's pension system is forecast to be fully funded till at least 2090, not something every country can claim. There are those that might quibble that bragging about the pension pot and also bragging about net debt is in effect double counting a single advantage, but it's something that most countries couldn't count even once.

It wasn't just the GST, of course. That basically fixed the government deficit trajectory, but the pension pot was built more by seeing the problem coming and hugely increasing payroll contributions starting in the 1980s and especially 1990s.

Jim