My 2013 car is not particularly laden with gizmos and has been very easy to repair (no real breakdowns...).
If you want a high-performance engine that meets modern emissions requirements, you're probably going to be looking at EFI and turbochargers. Changing the fuel injection maps on a modern car requires something akin to rooting/flashing an Android.
It's also federally illegal, I don't know why you've veered this thread into ease of performing illegal modifications.
The closest analog with smartphones to federal emissions laws is more like the FCC prohibiting hacking the baseband ostensibly to protect the cellular network.