Technology changes and you can either learn it or not.
Specialization of labor does make everything more complicated, but I'm glad I'm not having to grow my own vegetables or pump my own well water, despite the fact that I have no clue how modern farming or water treatment work. I suspect transportation will continue to become more specialized just like everything else.
An electric car, for all intents and purposes should be substantially easier to repair, diagnose, and work on, but manufacturers are doing things like using proprietary signaling protocols, locking out third party parts, and putting complex software in the place of simple and reliable hardware. Electric cars aren’t new, they’ve been around since the 90s and it was perfectly possible to create one without the “smart” nonsense we are seeing today. My car doesn’t need to report my location to a database or have a manufacturer kill-switch and it doesn’t make one a Luddite for feeling that way.
The 1890s, to be precise...
https://en.wikipedia.org/wiki/File:Thomas_Parker_Electric_ca...
Case in point, I have a former high school friend who runs a farm that’s about 50 acres as his primary business - without major machinery. They have quads and pickup trucks, but most applications where one would use a tractor are now done with animal power.
The result? It’s actually cheaper to operate as grass is cheaper than diesel. He’s not getting rich, but makes as decent living.
That's not the main problem with newer cars. The problem is that much of the required knowledge is intentionally kept proprietary so there is no way for regular people to fix it regardless of how much they want to learn it.
Only a tiny sliver of people need to understand how CAN actually works. Most Average-Joes just need to know how to connect (which is often done just via plugging into the OBD2 port, giving a keyed connector with power, ground, and at least one CAN bus).
As a hobby, I sell a low-volume device for a niche vehicle that works exactly this way. I assure that almost none of my users have any idea how a computer works, let alone anything physical on the CAN bus or what an MCP2515 or 120 ohm resistor is.