The power grids there are poorly managed. PG&E in Cali is constantly in court because their poor maintenance on the grid sparks many of the wildfires there. Most of the Texas grid is managed by a single company, and they don't draw power from outside their own grid unless they hit emergencies like what has happened the past couple years.
Also, anyone crying that more people owning EVs is going to take down the grid is basing their info off of extremes that have been politicized by the anti-EV people. It's basing it's numbers off everyone who owns an EV plugging a completely discharged battery into a supercharger at the exact same time. Which will never happen. For most owners, they use it for daily commute to/from work. Probably don't even discharge past halfway. They get and plug it in to their home chargers which are relatively low amp draw compared to commercial chargers, and will wake up the next morning to a 100% charged vehicle. The standard home EV charger uses less energy than your home A/C system.