Really? Modern engines are powerful and efficient because of complex systems like direct injection, variable valve timing and a wazoo of sensors that ensure that perfect air fuel ration. There are complex plumbing systems to ensure the ideal engine temperature that makes lean combustion possible. Multiple cams allow a smaller lighter engine to pump more air making it more powerful, this requires complex timing chains or belts that need replacing.That's bullshit and you know it.
That makes for a complex engine that is going to be difficult for a layman to troubleshoot. It also creates a lot of parts that may need replacing. Engines are built outside of the car and stuffed in leaving little room for access. You can improve access by making the engine bay bigger, but that will make for a larger, heavier and more expensive car. It will decrease performance, increase cost and apeal to less than 1% of consumers. You think auto companies install superfluous parts in cars for fun? those plastic engine covers that are about as difficult to remove as tupperware lids that people claim are there to prevent you from working on your engine is actually there to deaden valvetrain noise.
Now there are a bunch of complicated systems in cars that aren't necessary, navigation electric locks seats and windows, AWD, fancy touchscreens. Most manufactures offer simple stripped down version of their that may not have that stuff but they sell in very low numbers compared to higher trimmed models. People think they "need" AWD, navigation, engines with twice the head gaskets necessary and a bunch of doodads then complain when things are too complex when they break.
How many people buy Subarus because they need a vehicle that can drive in the snow, then they stay home the two times a year it actually snows?