Anecdotal - my neighbour has a 2019 Model X with some shenanigans going on with a sensor in the driver's side door. It has been going on more or less since the car was new, but parts are in short supply as it is (understandably, as long as the market lets them get away with it) more profitable to put the part in a new car than it is to perform a warranty repair.
On my 20-year old Land Cruiser, I recently had to replace the multi-function switch for adjusting the power mirrors. My local Toyota garage (on a small island off the Norwegian coast) didn't have it in stock, but next morning at 0851 a SMS ticked in, stating the part was ready for pickup - at a cost of less than $100 for the complete unit.
That kind of logistics organization is what Tesla will need in the long run. Building it is going to be very, very costly.
The overvaluation of tesla is just an extreme example of the overvaluation of the whole market. Every stock has a decade or two of growth baked into the current price instead of people paying what it is worth today. Tesla probably will be worth its stock price in less than 20 years, but why are we paying for future gains? What happened to the time value of money?