We're told that Emerence had a Cockney accent, as Noreen said, which I definitely find a bit odd. Aussie accents sound nothing like Cockney to me, and, even if they did, why would you use a term associated with the East End of London in connection with Australia?!
RP - received pronunciation. The Queen and Prince Charles are probably good examples now, but even they don't speak quite the way that 1950s BBC reporters did. Lucy Worsley's way of speaking isn't as posh as traditional RP, but attitudes changed in the 1960s and that very posh way of speaking is not as common amongst people younger than the CS generations: even Princes William and Harry don't speak what I would think of as RP.
There is a lot of confusion between accents, dialect and "good English": GO books often take the view that they're all part of the same thing. I speak with a regional accent, as do most people, and I sometimes use dialect words, but that doesn't mean that there's anything wrong with my grammar or syntax, or that I don't "speak nicely"
. Attitudes were different in CS times: we're told that Ros Lilley "spoke nicely", and it wouldn't have been uncommon then for aspirational parents to try to discourage children from speaking with a regional accent, or even to send them to elocution lessons. Now, there's much more of an "I am what I am" idea, and I think that a lot of us see our accents as part of who we are, because it means that people can tell where we're from
. Times change!
I do wonder if other countries have all these issues! I know Cristiano Ronaldo was teased and even bullied when he moved from Madeira to Lisbon, because apparently speaking with a Madeiran accent is seen in mainland Portugal as a sign of being a yokel and rather stupid. And GO books often speak about "Parisian French" as if using Occitan words or speaking with a Normandy accent or whatever is somehow inferior to that, and I gather that Tuscan is seen as being the most upmarket form of Italian. And the CS books make a lot of reference to Low German, "patois" and Schwyzerdutsch, and it's always the lower-classes who speak "Low German". But I don't know how much the idea of "RP" exists in other languages.