No, but only because it’s implicit rather than explicit. I’m not originally from the UK, but spent nearly 30 years living in England.
It’s still a very class-bound society.
It’s only more ‘obvious’ on Mn because people are explicitly starting threads about class shibboleths like what you say if you don’t hear what someone said, what you call the main room in your house where people might spend free time when not cooking or eating, what you call your evening meal, the size of your tv, where the way you decorate said house ‘places’ you socially etc etc, rather than silently registering these things and assigning you a social class, possibly largely or entirely unconsciously.