The social signifiers Americans would recognize distinguish between the main groupings of people who work for a living: working class, middle class, and professionals. On either side of that are the rich and the poor. Take a poor person, give them a lot of money and they become rich. Their interests, habits, or speech are irrelevant.
Some rich Americans who happen to have inherited their money distinguish themselves from outsiders through affections related to clothing and habits. The vast majority of their fellow citizens would not even recognize most of what this group regards as markers of group status, any more than they would be able to distinguish between this or that gang sign.
America's original sin is slavery. Skin color was a quite simple way to distinguish between castes, so there was no reason to develop the mannerisms that became important in Britain. Someone studying acting in the UK will likely spend a tremendous amount of time on voice, so they can navigate the complexities of representing a variety of classes. It's not accidental that Americans are more noted for a much more inwardly focused "method".
British. Very, very British.