With proportional representation a politician could neglect anyone living more than a 2 hour drive from the US border
What is the logic behind this? Are you just inventing stuff?
Something like 90% of Canadians live with 2 hours of the US border, so you could in principle get a 90% majority government even if everyone living +2 hours away voted against you. That wouldn't be possible with the current system. Our current system allows people in northern areas to still have a say, even though they only make up a small fraction of Canadians. Things like this are the reason why the current system was designed the way it was.