> Would anyone here allow their Tesla to discharge when parked, allow it to feed power back into the grid?
I absolutely would, in fact it's a major reason I am not getting a Tesla and am instead opting for an EV that emphasizes its vehicle-to-home power capabilities (e.g. F150 Lightning and Lucid). I also know a ton of other Texans who feel the same way I do given our (deserved) lack of faith in our electric grid.
Also, saying it's "feeding power back to the grid", while technically accurate, isn't necessarily how I think this will be messaged. Instead, I think it will be messaged that, in times of high demand, your house alone will be powered by your car battery and taken "off grid".
Right now, some of the biggest issues with renewables is just timing during the day (e.g. late afternoon/early evening power needs peak right as the sun is setting). Telling people they'll get a substantially discounted rate if they allow their house to be "disconnected" from the grid for a few hours (because they have a car battery that can power their house) would be a big incentive to a lot of people.