Early electronics were incredibly simple, and any idiot with a soldering iron can repair them. Who repairs modern TVs? Well, you don't, you throw the PCB or screen away and fit a new one, which again is easy to do (well, the PCB is anyway!).
It's a good point, but EVs have an awful lot of proprietary software and hardware controlling them. That kind of stuff isn't going to be made available now, or ever. In fairness the same applies with modern cars and ECUs, but an engine is an engine and up to a point you can easily go standalone. I do not believe that will ever be the case with EVs and their complex systems, as to reverse engineer that is going to be a nightmare if not impossible.