Interesting. But my original point stands: if you don't sell your car, you're looking at a $20k bill a few years down the line, and on the page Tesla are happy to talk about total-cost-of-ownership of their competitors, they're not telling you about that $20k replacement.
No reason to think it will be dramatically different from the cost now. With technology, the cost typically remains constant, while capability improves. The battery you need to buy in 10 years may be a lot better than the one you have now, but it won't likely be much cheaper.
