> The fact that the owner can keep it going is a testament to the maintainability of combustion engines that don't have high tech computers in them.
New engines with modern ECUs are every bit as maintainable.
The ECU doesn’t make an engine less maintainable. Modern engines would have more moving pieces such as variable valve timing but otherwise they’re very similar in concept and maintenance.
One part of maintainability is cost. And a simpler mechanical engine without proprietary ECUs is going to be cheaper to maintain, provided parts are available.
If someone encounters issues with an ECU and it needs replacement at $1k-2k they might just consider the costs and that being a down payment on a new vehicle vs. repairing. Labor costs more than parts for complicated electrical/computer/engine problems. Electrical issues in modern vehicles don't appear to be easy to troubleshoot, sometimes require proprietary tools. A simpler mechanical engine could be DIY repaired and running, check out the "low-buck garage" youtube channel and the $2 Jeep series as an example.
I'm not advocating something like going back to computer-less, inefficient, stinky, loud cars, just pointing out that when we add computers to things, it makes them less maintainable to the average person.