Fair Housing rules, specifically the Fair Housing Act is a clearly necessary and effective measure for combatting housing discrimination based on ethnicity and economic class. Most importantly, it deals with discrimination in government backed loans and housing access discrimination, and I don't disagree with Herring's support for the Act.
But to clarify, the Trump administration did not repeal the Fair Housing Act, they repealed a provision that was dormant for the first half-century that the act existed, the Affirmatively Furthering Fair Housing (AFFH) provision. The reason why this provision of the act was never enacted is that no administration, including the poor-and-minority-supportive administrations of Carter and Clinton, is that the provision isn't really workable or beneficial.
As the name suggests, AFFH is basically Affirmative Action for housing. A common example that was used to support the AFFH was addressing the issue of poorly performing schools in low income, often urban areas. What the AFFH does is to fund housing to move some of the students in the under-performing schools to an area with better schools. This of course does nothing to improve the schools that the rest of the kids are still attending, so instead of spending those funds to improve the school for all the kids in the school, it's using it send a relatively small portion of the kids to other schools, it's essentially private school vouchers. Even worse, the families that will most likely be able to move to the suburban low-income housing are the ones most likely to be keeping the under-performing school's tax base afloat, essentially taking a struggling school and making it struggle even more.
Then there's the issue of the AFFH effectively offering financial incentive for developers to gentrify urban areas, to move lower income and minority residents to areas with fewer services, transportation options, etc