That doesn't seem particularly unfair. If you can image a scenario where someone buy Apple at $1, and it's now worth $1,000. They just leave Canada, pay no tax, then sell in a low tax jurisdiction.

However, it can be a massive pain in the ass for illiquid assets or assets you don't intend to sell at that point in time. A good example might be a pension. Getting hit with a tens of thousand dollar tax bill for a pension you won't receive for another 2 decades is painful.

Also, Canadian laws don't stop at the border as a citizen... so breaking laws in other places still puts you in legal peril for extradition.

Notably, corporate tax rates are often much lower in Canada, and export free trade is available with most trading partners. Note the US taxes on citizenship regardless of where you live (or if you hold multiple citizenship), and failure to file your IRS statement was an $8k fine last I heard. The fine often stays even if you owe the IRS $0, and temporarily live in another region.

The TLDR version: talk with corporate tax accountants in each region before filing, and do not assume the late tax filing fines will magically not apply to your situation. AMCHAM will usually help guide investors on their filing obligations for type C corporations in the US. =3