Thats actually partially incorrect. The power companies designate certain zones critical infrastructure that they don't turn power off at. This includes hospital, fire, police, grocery, and government buildings. If you live close enough to that zone, your power stays on too.
Because of the amount of power they had to save, some areas like mine bounced between two zones. Some areas had to turn every house off but critical infrastructure. I had 1 hour on 1 hour off. Now if the police/fire are all in nice areas, that would be why the power wasn't turned off. It wasn't specific racism of turning power off at low income areas but institutional racism as they didn't have grocery ,police station, hospital, or fire station in that area. I live in a nice area. I was still turned off. My sister lives near a retirement home. Her power was never turned off
The AAC where the Dallas Mavericks and Dallas Stars play is a shelter in event of emergency. It was listed critical infrastructure. When everyone was out of power, they were still going to play a game. It wasn't until everyone screamed waste of power, did the mayor get involved stating the stadium is a shelter and critical infrastructure and we should be using it for a game.