The whole regional accent sounds like something else, which I’ve seen in pretty much all countries I lived in.
In the UK I would say that’s the RP (i.e. Received Pronounciation) English accent, is what one would think of as an “educated” accent, or in other words the “TV accent” - the non-regional accents of most TV anchors - though nowadays regional accents on TV are much more common, in the UK and elsewhere.
What I’m talking about is often called “Posh English” and it very much signals high-class rather than merelly high-education, and it’s common amonsgt those who as teenagers frequented certain private very expensive boarding schools (curiously called “public schools” in the UK, not because they’re state schools but because theoretically anybody who can afford them can send their children there, though the reality isn’t quite like that).
RP would be a middle class accent, whilst a Posh accent signals being upper class (typically old wealth).
I’ve lived in a couple of countries and Britain is the only one where I’ve noticed that an exclusive upper class accent is part of how the upper classes signal their social status.
PS: By the way, I absolutelly agree with your point about being yourself and not trying to immitate some self-proclaimed elite and their manners, and follow the same myself. In my case, living abroad for over 2 decades has really given me an outside perspective on just how tiny and silly such local differences really are and how profoundly ignorant it is to feel “elite” based on such social theatre which is totally irrelevant in measuring the true qualities of a person.