If someone said you could live in one of the most desirable places in the entire world on an 'ordinary' job but you had to share a room (which TBH could just be your significant other anyway) that would seem like a great deal right?
When many categories of essential workers start to be priced out of living locally and need to commute long distances from undesirable far-flung suburbs, it is (a) a grossly inefficient use of resources, and (b) makes the city much less pleasant and effective. A city where all of the residents are wealthy professionals with other workers as second-class commuters is not a very nice place to live, more like a theme park or resort hotel than a real city.
i.e There is pressure for people living in that area or moving into that area to find a SO or something similar.