In many languages, there is indeed a bias against the non-official dialects, or whatever that is not the dialect spoken by the capital's inhabitants.
But not all "capital dialects" get this break.
Examples:
London. It is well known there are several London accents. Some are considered really hip, or street. Well, some are even incomprehensible, at least to me.
Paris. Again, there is the gouaille, or the Parigo, an intensely "street" version of French. Arletty was its ambassador.
See this
lively thread on the Parigot take.
But many - maybe most - in France recognize the Loire French to be the nicest-sounding.
In Chinese, the local Beijing Mandarin accent is sort of the Chinese gouaille. It is considered very "street" but not necessarily attractive to the ear, what with the automatic linguistic suffix of "rrrrrr" at the end of every sentence.
In the 90s, I actually saw youngsters in Beijing karaoke joints faking a Cantonese accent when they sang, because the big-time singers then were from Hong Kong, and thereret the Cantonese accent (spoken in HK) was somehow considered hip.
In Beijing in those years I once even saw ads where people (touting cars? fridges?) also adopted a fake Cantonese accent to convey they were used to a certain spending power, LOL. (That fake Cantonese accent fad seems to be gone now. I wonder which is the hip accent for the Middle Kingdom now.)
After pointing out instances where a capital's dialect does not always enjoy cultural supermacy, I also want to point out a dismaying phenomenon. Several times I noticed - on ST and elsewhere - that when people mention that a difference of accents exists, they are attacked for being prejudiced. Sigh, the difference of accents is plain to anyone with ears. Noticing it just means our ears are still working and does not mean we are judgmental.
