To be honest, it doesn't have to be HSR at that point. Just reliable normal rail would do that, something we're still lacking for most of the country. Imagine being able to get to any province in a day under $30 (and even cheaper group deals) with zero chances of any delays.

Vacations across Canada, or even just visiting family in another province for a weekend would be easy and regular. Not to mention how much it would bring the nation together. As things stand, the provinces are more separated from each other than the states in the US. We're closer to the EU than the US in terms of unity. Arguably even worse than the EU. Promoting cross provincial movement for even little things would seriously bring us together, not to mention all the economic benefits.