iPhones aren’t particularly difficult to repair. 50 bucks in tools and you’re pretty much ready to become the ultimate parts swapper. The waterproof seal takes like 3 minutes to clean up and replace.
Apple certainly doesn’t encourage third party repair, obviously won’t warranty items that have been opened up, and tries to throw some curveballs but the aftermarket is so huge they always find a solution. The same can be said for their software, which is constantly unlocked despite their efforts against it.
Everything can be repaired cost effectively (due to economy of scale, unless it is designed wrong) if the volume is high enough.
Back then I heard complains about people cannot replace the glue tape between battery and the screen, then they just throw you a new one, or new tools to do all those repair. They also said about touch screen and glass being not separable but these days they just throw in a new touch screen with the glass.
The problem with Tesla IMO is really they don't want to be a car company that support things for generation, but rather they want to build new things and discontinue the old (think Apple). I don't buy Apple or Tesla mainly for this reason and if I do I certainly won't expect it to be a PC I build or a Toyota. When volume is low and demand is high manufacturers can be quite an ass to deal with, and they can get away with it, as you can see.
Regarding to Tesla since the insurance companies hate them (double repair cost, long parts wait, lack of parts), they would eventually turn into a "this car cost double to insure" category. Since Tesla offers their own insurance for their own cars you definitely should insure with them. They are running a scheme to artificially reduce the insurance cost to make their cars look cheaper to own than it really is, so take advantage of it.