Earlier quoted context omitted.
I think you're confusing with having a united Canadian identity/culture/nation (à-la-PE Trudeau). Also, nowadays, you probably want to speak more than two languages, or at least have some understanding of more than two languages. I'm always amazed by how many people in the US speak either French or Spanish or both (although, sure I have a very biased experience, being in tech circles). Tear down walls, speak multiple…
Why exactly would you want to speak several languages, if your interlocutor speaks English? I'm French and I'm not religious about the French language itself. Everything would be so much simpler, including sharing cultural differences if all of humanity just spoke the same language. English is the interop layer of human communication. It has imperfections but one imperfect standard is better than hundred or thousand…
People are afraid that local identities would be lost. Be the reason people stopped speaking their local language is because most of them don't see a benefit in it. We need to stop the romantic tale and get real.