I attended two French Immersion schools in B.C. between 1988-1996 and this article doesn't line up at all with my (admittedly anecdotal) experience.
I'm not your typical French Immersion defender, I hated French Immersion as a kid. I attended hybrid schools where only maybe 1/4th of the school was French Immersion and the rest were English and it made me and my French classmates targets for bullying. The parents of the English students, for whatever reason, didn't want French Immersion in their schools and as such there was a lot of resentment passed down. It wasn't unusual for me to have to fight my way home, being outnumbered 3-to-1 by English students who didn't want French kids in their school. Maybe they thought it was elitist, but that couldn't be further from what I observed.
I was raised in a middle-to-lower class household, the only reason I was in French Immersion was my mother was a Quebecois transplant and didn't want me to loose touch with the French-Canadian side of my family. Most of my French classmates were also on the lower end of the income spectrum, with only a few exceptions.
I never saw it as an economic issue. If anything, the biggest differentiator between the English and French kids was the involvement of their parents in their school activities. The Parent-Teacher events by the French Immersion parents were typically packed, whereas the English PT events were sparsely attended, regardless of income levels. It just seemed like the French Immersion parents took a more engaged approach to their children's education and participation in French Immersion was more correlation than causation.
I have no doubt that there are highly sought after public schools with waiting lists and such. But if anyone thinks there's some special treatment for the French Immersion students in Western Canada, then they clearly have only looked into it on the most superficial levels or have an anti-French bias. The special treatment is you have to do every class in French (except English class) and you get beat up for the privilege.
I guess parents who care about their children's education are elitist. How dare they.