I totally see your point. I also keep cars long term (typ 8-10 years). I think the main difference between us is that I don't (personally) place much value on the peace of mind offered by an extended warranty. I tend to look at them in purely fiscal terms, where the cost of the warranty is greater than the expected value of the repairs (essentially, you are buying an insurance policy). I'd rather "self insure" (or "roll the dice", your choice :wink.I think you and I see extended warranties differently. We don't necessarily look to an extended warranty to just protect us from any past negligence or defects but to offer us complete peace of mind for repairs. We also usually keep our cars for about 6 years so 4 years of coverage is not sufficient for us and this is where the thread's topic of Tesla not selling an extended warranty to anyone but the original owner comes in. Every other car manufacturer we have bought cars from offers the extension of the warranty at additional cost. Mercedes for example allows you to extend the CPO warranty for up to 7 years.
But I tend to do all my own maintenance and minor repairs, and I know trusted independent shops for major work (I never go to the dealer once the warranty ends), so that probably plays into the peace of mind thing.
With a used S, I'd probably lean towards getting an extended warranty (if possible) since doing my own work/going to an independent shop isn't really an option (yet).