If travel dropped by an order of magnitude, and 3.9 million Canadians traveled to the USA, that's 200 people in 3,900,000, a bit less than 1 in 19,000. On a national scale that's obviously a concerning number, but on an individual scale, I'm not sure personal exposure to that risk will change all that many people's decisions. Those who it does change likely perceive themselves at higher risk than the average Canadian.

That's assuming it's a good estimate, but I suspect from numbers I've seen on flight traffic drops, this is an overestimate; likely more Canadians traveled to the USA, and so the individual risk is even lower.