Any kind of social difference can make a difference and be reflected in speech. People notice things and react to people by their speech. Has always been true: In Bible: the shibboleth and its pronunciation was used to discern differences; the recognition of Peter the Apostle (as a Galilean) when Jesus was being arrested, etc. In classical Sanskrit plays, e.g. Shakuntala, high noble people spoke Sanskrit, women, servants, children spoke Prakrits.
This chart shows increasing use of [r] postvocalically, such as in words like car, beer etc., in five different styles (A to D', D' being the most careful), by people from different social 'classes'. Note that Lower Middle Class speakers (LMC) cross over all classes above them and use the most r-ful speech in the most careful style.
Another chart shows the reduction of the use of stops and affricates instead of 'th', also by class and style, in other words, the reduction of forms stigmatized as deze, dem, doze which are replaced by these, them, those etc. .
The type of official State policy may determine kind of attitudes toward dialects, both regional and social.
Compare the premise of social dialectology (sociolinguistics): language is inherently variable.
Studied and isolated variables, e.g. /r/ dropping in NY, vowel-raising in NY. Centralization of /au/ in M's Vineyard; other variables (e.g. be) in BEV.
For your interest, here is a page devoted to Scottish dialects, and all the sociolinguistic baggage associated with that area of Britain. The site indicates that people are tired of 'dodgy' (i.e. inauthentic) Scottish accents, such as the one Mel Gibson used in Braveheart and now are providing resources to help people learn an authentic one.
Allo, bonjour! J'espere que je vous dérange pas?
( Hello! I hope I'm not bothering you?)