"The other way" described in the article looks like this: government insured private mortgages depending on racial build of the neighborhood, with the best insurance available only to white-only ones, and none available to ones when black people lived, so the government artificially lowered costs for white people buying in white neighborhoods and created a huge cost (and disincentive) to allow any non-white people to enter those neighborhoods, however rich and financially stable by themselves they might be.

How exactly this is an example that proves necessity of government regulating private rentals?