You might not know who yours is, but plenty of people do.

To be clear, I'm in politics "like a dirty shirt". I definitely do. Most people I know wouldn't off the top of their head, and the people who's doors I knock on are prone to not even understanding that there's multiple levels of government.

It’s easier to say “write to your MP” than to say “write to a whole bunch of MPs. Which ones? I dunno, all of them I guess?”

That's definitely true. My local guy uses those letters as toilet paper, probably, but the ones in unsafe ridings or who are young and idealistic might actually care. I have to assume there would be alternatives that grow up, though, including petition signing which is already quite prominent here.

As for keeping out unpopular individuals, that's true, although Justin Trudeau himself is the only person in my country right now with that kind of notoriety.