@afewbugs @astronomerritt Kate Fox's _Watching the English_ (2004) may get into this, it's been a long time since I read it.
There *is* a similar class (socioeconomic status) system in North America (see e.g. WASPs, trailer trash), but it's not as rigid and doesn't have that history of aristocracy, landed gentry, etc. However, just as many North Americans pretend not to "see race" and, if they must, reduce it simply to "skin colour", they also "don't see class" or, when they do, reduce it simply to one's income, as if a lower-class "new money" person were of the same class as a moneyed WASP who went to a prestigious private school.
Paul Fussell's Living Room Scale from _Class_ (1983) is by now rather dated but gives you an idea: https://pigtown-design.blogspot.com/2011/03/living-room-scale.html
—yours, lower-middle