In the household that I grew up in 3 languages were spoken. What people didn't do is bring it into the workplace or a public setting. In fact (I wasn't there, of course) but in both my mom's and father's, when they were kids, no one spoke anything other than English at the dinner table - reason, because they were learning that language spoken in the country and the culture - not trying to supplant it. They were grateful for the opportunity they had in the USA, and wanted to be part of it, not separate as so many hispanics do. I worked with a hispanic guy who had been with the company for over 20 years and refused to speak English so that whenever he needed to be spoken to a translator had to be summoned. Don't ask me why he was allowed to get away with that shit. I mean - do you think that an English speaking person should feel so entitled as to go work in another country, and not speak the native language? How do you suppose that would go over? In the company that I retired from, which was French owned, and many of the people there of all ranks were French speakers it was company policy that only English be spoken. The reason is obvious - it's a business where people need to communicate effectively in a common language. That's just common sense.
I think in the USA about 120 languages are spoken. Do you think the native population should have to learn 120 languages to accommodate immigrant people, or that immigrant people should need to learn and speak the native language?