Sounds like you haven't researched this well enough. You are basing all your conclusions on how things are right now without considering the rapid technological development going on.
It is all about volume and when there is a large fleet of EVs it will be far more economically interesting to build up solutions which can utilize the battery capacity of these cars. When you got very low number of EVs that is less interesting.
1. Tesla isn't officially supporting bidirectional charging in any of their vechicles, so that isn't exactly surprising. But bidirectional charging is becomming more prevalent.
2. Maybe where you live but that is certainly not the case here in Norway where 90% of new cars sold are electric. You ignore technological development. Million-mile batteries are comming and those will make it irrelevant how many times you cycle. Your car will die long before the battery.
3. You really haven't thought about this have you? With large amounts of renewables in the grid, prices will fluctuate a lot more through the day. You will buy cheap when the sun shines and the wind blows. You will sell at high price when renewables are not producing much. Yes, of course this relies on legislation and practices which allows those fluctuations, and it relies on smart systems to buy and sell automatically at favorable times. But that is technologicallly feasable.
4. As as I said with a million-mile battery, you will not manage to degrade the battery before the car itself dies. And again prices will fluctuate a lot when renewables dominate. Thus you will buy and sell with more profit than you project.
Read up on million mile batteries:
