It's called the Magnuson-Moss Warranty Act in the US. Tesla doesn't want to be bound by it, so they are forced to not require service as a condition of maintaining the warranty. Separately, the state of Massachusetts has a "right to repair" law, that requires Tesla to make service information available to owners that they very reluctantly (read exorbitant $$$ to owners for access) do. Several other states are considering similar legislation.
It's an incredibly egregious attitude by Tesla.
I think we agree.
The lack of a formal obligation to have the car serviced to maintain warranty is not necessarily a good indication that servicing is not required, but only that the car will get past 50k miles without servicing before it falls apart except for a battery and 1 or 2 electric motors depending on model.