Part of the round-robin in this thread is because there is confusion in North America as to the relationships between prestigious, work of significance, income, and education. Indeed many levels of work requiring but a Secondary School diploma are of great significance - firefighters, police officer, plow truck drivers, but few people would say that it would be a step up in life for Donald Trump to drive a plow truck or for the senior partners at McMillan Binch Mendelsohn to become Police Officers. At the same time it’s not entirely about income, if so would not the CEO and Chairman of the Board of ExxonMobil top the list. Nor for that matter is it entirely about education (although there is a much stronger connection) if so would not University faculty most of whom have Research Doctorates top the list.
It is the very combination of factors which makes it so subjective and hard to nail down.