And it did. Plenty of Texans were reducing their power usage to the absolute bare minimum once they got word of how expensive power had just become.
Really it looks like retail electric providers in Texas are structurally disadvantaged vs generators, carrying an unlimited obligation of service vs getting the spot price set to the regulatory maximum.
I've also discovered over the past week that there's at least one more wholesale-rate provider, https://www.octopusenergy.com (specifically, it's OctoFlex plan).