I think the thread is suffering from mass confusion between household income and personal income, to be honest. Household income of over 100k is, as we’ve seen, relatively common. Personal income over 100k is not.
Remember that personal income is not evenly distributed — wealthier people tend to marry other wealthier people. If one member of a couple earns more than 60k, there is an excellent chance that the other will earn more than 40k. And those kind of levels of income are not that uncommon in London (hence the preposterous house prices — the average mortgage payment in London is an astonishing 75% of the average wage).