The notion that people who possess certain distinctive trait and share them between each other aren't going to have certain shared experience that form a deeper bond between several of them (not all of them, but several of them) than between them and people with whom they don'T share this is a risible notion in and of itself.
If that deeper bond exist between a large enough group, then yes, a distinct community exist within the state.
Your first sentence was tough to parse, but I think I agree with you.
I don't care to force the Chinese Canadian community to watch more hockey and eat more bacon. If they all want to live close to eachother (in some scenarios, a la Chinatown), have a whole bunch of stores that sell things they're interested in near eachother, and so on, all the power to them.
I think it would be weird if a bunch of Polish people immigrated to the same city in Canada and didn't at some point agree to open a store that sells Polish bread and other foodstuffs, maybe a Polish school, church, and so on. Canada is a land where you're free to do what you want, within reason. Of course people are going to do things like that.
Is it hurting Canada? In some cases, maybe, but in most, nope. I would say in most cases it enriches the country.
The problem is that most people have an 18th/19th century nationalistic type opinions on what a country should be. So then they look at a country like Canada, and can't figure out how ethnic "enclaves" might be beneficial at all. Well, they can be, and in a lot of cases they are.
What's important to remember is that the kids born to people who come over here and maybe don't even learn English, those kids integrate with Canadian society very well. They are more "Canadian". For the most part.
We don't have much ethnic violence either.. it's not a problem.