I think the proposition that anonymity can be important in facilitating political expression is a really good point. I think that applies in Canada too, in certain circumstances. I would draw the line where, if you're spending money on something that counts as election advertising under the definition of the Elections Act, then there should be some verification of the source, that it's a real person and a domestic actor who is behind it. It's different if you just want to express yourself, say, politically on Twitter and criticize a politician. There is value in allowing anonymity there.
That's where I would draw the line. That can be a difficult one to enforce, potentially. If you're spending money on advertising, then the public should have a right to know.