I can totally understand the frustration...for my MYLR, I waited 84 days to get a VIN. That seems excessive, but these are not really "normal" times, either. In addition to actual shortages of materials, there are issues with shipping and trucking and so many other things. There is only me and I have a car that I will sell once I have the MY (and I live fairly rurally, so would NOT have been able to be car-less for any length of time). I too, was ready to give up and cancel my order and stick with my ICE car...I did NOT want to learn to drive a Tesla in a Michigan winter in a snow belt county that does not believe in plowing the roads!
You have to do what works for you, but I will reiterate what you undoubtedly already know: used car prices are still high, even if coming down, and most other manufacturers are having similar problems with delivery times. I think that having a deadline for how long you can wait is realistic at this point. What is your backup plan for a different car? That is not any kind of dig, I am just curious, as I personally really wanted an EV car, and the Tesla charging network was important enough to my needs that other model EVs really were not an option.