I absolutely agree, I have to deal with way too many parking garages with those huge columns placed at the "entrance" to the spots, or in areas with shorter obstacles such as flower beds or really tall curbs. A surround view camera can also enable unique angles such as passenger side front wheel cam allowing you to park in home garages. A lot of newer houses are built with 2 car garages that are 20% smaller than houses built in the 90s.
I'd say in general I agree that Add-ons don't really help preserve value of the car, but in this case it's not an add-on, but rather a significant tangible design change across the lineup. This is like Model S' Oct 2016 refresh with the 8 camera setup that made the car relevant for the next 6+ years, while a Model S made in early 2016 immediately became obsolete.
I think at this point we only know that S/X will get the new HW4.0 package, but even now I don't know if it's indeed going to get all those cameras, I'm in the opinion that S/X will get HW4 computer and some upgraded cameras but not all the bumper ones, this is how they're able to push cars out without production stoppage. Looks like at least the repeater cameras now point to the sides more than pointing to the rear.
HW4 will greatly enhance AP performance in adverse weather conditions over HW3- cars (minus means no radar, no USS), AP speed is limited to 85mph but TACC allows higher speed, following distance limitation also made it a pain to use in rush hour traffic. I wish Tesla will turn radar back on for pre-vision HW3 cars to restore that capability.