1. We simply don't know if there are savings. If the getting ready for reuse costs almost as much as a new rocket, they might as well use a new one. Not to mention we will only know how many times they can be reused when they finally fail. Now had they already reused any of their rockets 10+ times, I would say, sure, it is proven. So far the most was reused only once iirc.
2. I agree that EVs have not got enough energy density. But if so, they shouldn't make silly claims. You can't beat the law of physics. Maybe sometimes in the future.
3. Boring hasn't bored anything useful so far. They have some contracts to bore, but we shall see what comes out of them.