I think you hit the nail on the head. That's the problem of having a multicultural system enshrined. I support an intercultural system, kinda like what Quebec does.
I've been to Vancouver, though, and people in the third generation almost always speak English, but even then, they still seemed to be trapped in ethnic enclaves (like Chinatowns).
When people come to Canada, I don't believe most of them want to just live in their old country with the same sorts of things (which is what happens in big city ethnic enclaves in Canada).