It's just a matter of definitions as we see them. The multiculturalism I am thinking about is essentially the melting pot -- multiple cultures contribute to the culture in general. We have always welcomed new cultures, and the their best has spread to the rest of society. That is how America is and one reason it is great.
It's not perfect though, as we've long had "Chinatown" and/or "Little Italy" in many major cities. We accepted them for the most part. So now we're getting "Little Mecca" in places. Big deal, as long as they don't try to force acceptance beyond their willing own within their little enclaves. We don't have to respect their culture, but we should respect their rights as Americans to associate as they wish.
Maybe my definition is off, causing this confusion, but that's my point.
I see your point, and I do think it is a matter of linguistic precision. I think we all agree on this.