Britain has moved in my lifetime from a significantly manufacturing based economy to one in which the service sector is of greater importance. The former was labour intensive, the latter far less so. Not just fewer workers per unit of output but different types of employee. The quite rigid social divisions of the previous structure have become blurred to the point of irrelevance.
We are all “working people” whether we wear overalls and do repetitive manual tasks or wear a suit and have an office in Canary Wharf. There has been significant social mobility but, arguably, not enough. The reluctance to move to where the best jobs are (in London and the South East) is often based on the practical consideration that it’s unaffordable to do so.

So the old class structure, once illustrated wittily but accurately by Cleese, Barker and Corbett on the Frost report, has largely disappeared. In its place is a hierarchy based on location. The best careers are in London – and Received Pronunciation is the language of the City. Those brave enough to move from a northern town or city to Surrey tend to lose their accent along the way.