It would save us both much time if you READ my posts before responding.

Received Pronunciation was a regional, not class, development largely complete BEFORE the British first colonized America: Brits in 1800 London AND Virginia were about equally likely to have an RP accent. "Equally likely" in this case means "not very," since <10% of the UK uses RP even NOW. It never had anything to do with stratifying society either, rather, with the impossible task of standarizing the language, ironically, by masking and neutralizing a speakers native regional accent (even though RP is itself a mainly regional development.) As one scholar put it, "It is the business of educated people to speak so that no-one may be able to tell in what county their childhood was passed."

The advent of radio and television (especially the first) encouraged that view because broadcasts throughout whole nations had to be accessible to an entire audience that spoke in myriad dialect and accents. The Middle Atlantic was developed and promoted around that time on BOTH sides of the Pond, for similar reasons, basically, so no one felt like the anchormen and entertainers on whose ratings networks depended were "foreigners." Imagine claims of "liberal media bias" if every anchor sounded like a Kennedy instead of speaking a bland generic English.

We are not talking about pidgin English, but there are many gradations between it and full fluency: According to that same e-arbiter, fluent speakers are only a QUARTER of Indians capable of normal English conversation (i.e. NOT merely broken non-standard English.) https://en.wikipedia.org/wiki/List_of_countries_by_English-speaking_population

There is a difference between non-standard speech and the mostly uniform standard of a different DIALECT: The crux of this discussion. GLOBALLY, an estimated 1.2 billion people speak English well enough for normal conversation; within the US, 300 million use over THIRTY distinct dialects: At MOST maybe 30 million Americans speak any particular dialect; should we really believe those 30 million a plurality of 1200 million English speakers?