I used to work with a Mexican girl whose father used to yell at her for speaking Spanish.
“No, no, NO! You are in America. You are an American now. You MUST speak English!”
That was the attitude of my 9legal) immigrant grandparents.
At home they spoke the mother tongue, but around Americans and out in public, it was English, no matter how difficult it was.
It was both pride and courtesy.
They were in American and Americans, and they didn’t want someone to think they were talking about them behind their backs.
That was class from a bunch of dirt poor peasant farmers.