Corbets, you can disagree all you want, but it's right there on Tesla's site. There is absolutely no requirement to perform the annual services in order to buy an Extended Warranty. The only caveat is that once you do buy the Extended Warranty and are in that warranty period, your coverage MIGHT be affected if you don't follow the recommended services.
If I choose not to service my Tesla vehicle, will this void my warranty?
It is highly recommended that you service your Model S or Model X every 12 months or 12,500 miles (20,000 km), whichever comes first. If you do not follow this recommendation, your New Vehicle Limited Warranty will not be affected. During the agreement period of the Extended Service Agreement, your coverage may be affected if recommended service is not performed. See the Extended Service Agreement Terms and Conditions for further details.