If you don't think rural America would trade those subsidies in the blink of an eye for the dissolution of those cities into their own separate union or something, you really don't know rural America.
> But why should the minority get to dictate policies if the majority?
Because a few pinprick-sized geographical locations overflowing with millions of people who think that's how everyone should live / does live (it's not) shouldn't get to dictate the policies of the entire rest of the country that is living in relative peace and comfort away from such overpopulated, crime-ridden areas with extremely high costs of living and an overall terrible QoL. Look at any US-wide election map, by county; see how few areas are truly blue. The homogeneous state of southern California should not get to decide how the rest of us live/suffer.
The founders knew what they were doing.