[Aerkuld]

This is a good question.
Not that I'm in the repair business, but the same thought has crossed my mind. Vehicles seem to be getting more and more software reliant and brand specific as a result. Ford have their system, Chrysler have a different one, Chevrolet is different again etc. Sure, OBDII is universal on a basic fault reporting level, but to diagnose a specific fault I think it will become necessary to have a specific diagnostic system rather than a generic interface. The other problem I see is how reliable modern cars have become, and this is only going to increase if the shift to electric vehicles happens. In the future I think the dealers are going to become the only ones who can work on their vehicles for major systems. Maybe you'll have specialist independents for a specific brand, but this shift toward dealer-only maintenance is deliberate and orchestrated by the manufacturers. Maybe the future of automotive repair will be more in the hands of software engineers who can hack in to the manufacturers systems?
On the other hand, I imagine there will always be a need for shops to do wheel bearing replacements, driveshaft joints, suspension work, etc.