There's almost 0 state efforts to preserve the cultural identities of immigrants of any kind
When people celebrate "diversity" in the West, it's just eating shawarma, drinking boba, watching Anime, listening to kpop, and eating at an Ethiopian restaurant. Pure commodification and consumerism masquerading as celebration and promotion of foreign cultures
Or you'll have people fetishizing about spicy latinas, lightskins, and Asians like they're fucking Pokemon cards
its not really society being fluid, a lot of those regional dialects were actively suppressed, especially the ones associated with poverty/immigrants/rural areas. my dad and grandma talk about getting beaten by teachers for their broad [redacted] dialect and accent (which doubtless i have much less of than they did, but even i was criticized and marked down for it) and for decades you couldn't be on british radio or tv speaking anything other than RP, which spread a very specific idea of "correct" english across the country.
Yeah, have some family in England who were beaten or had soap literally shoved in their mouths if they spoke any angloromani.