Instead of requiring weatherization, they allowed power plants to opt out.
Lawmakers on the Senate Business and Commerce Committee were frustrated that the new law allows natural gas companies to opt out of weatherization requirements if they don’t voluntarily declare themselves to be “critical infrastructure” with the state.
https://www.texastribune.org/2021/09/28/texas-power-grid-loophole/
I just let that mission fail and got on with the rest of the game. I’ll do it next time I play the game though.