If you took the same amount of high earners and dropped them in an area with five times as many equivalent utility houses, then prices would not be high even though there are the same number of high earners. Hence high housing prices are not a result of a population of high earners simply existing.
As an example, I can afford and am willing to pay $5 for an apple, but I will not because I can easily find an equivalent one for $1.5.