The right of access and the right to housing are not affected. The police will not evict a person of colour from a rented accommodation, and will not assist a shop owner with kicking out a person of colour from their shop.
But a right is not an entitlement. In order to rent a private room or buy something in a private shop, both parties should agree.
Again, quoting the convention, "equality before the law". A business owner is not a representative of the law. The police and the civil servants treat everyone equally.
>In where you live, and where you used to live, a business can refuse service to a minority group?
A private business can refuse anyone. That's because it is private. "The transaction is not seen as profitable." The most popular reason for refusal though is not race, origin, or citizenship, it's not having an app to pay for the service, because most small businesses don't bother accepting cash any more. The government is theoretically trying to deal with this issue by running propaganda campaigns "accept cash!", but I think the battle is lost.
>Real ID is a US-only issue, so I interpreted "If you are worried that your tenant might happen to be an illegal migrant" in the US context.
Yes, I got confused, apologies. I still don't see why the US cannot just issue passports to all citizens, and treat a passport as a universal ID (or mandate that all state-issued IDs be universally recognized), but it's unrelated to the "Real ID".