Forcing other people who have a shared language to not speak that language to each other sounds more divisive than allowing people to speak to each other in whatever they want to.
But honestly why would you care? Does it bother you that you're unable to eavesdrop on a conversation you have no part in? If they want to speak to you, then they'll speak English.
Also I didn't notice anywhere in my post that suggested people shouldn't learn to speak English. You put that up as a strawman argument.
On a completely unrelated note, I was scrolling down the article and saw a big X and clicked it thinking it was a popup or ad and hit it out of habit, but it was actually the embedded tweet.
Another reason why the X rebrand is dumb.