Some of these sound like upsides to me. I've owned a lot of older cars, and they're always a mystery box of "what will fail next?". So many moving parts, and they're often hard to diagnose.
Based on your comment, I expect newer cars to have lower maintenance and repair costs, fewer part failures, and less guessing about exactly which part is broken.
Newer cars do have lower maintenance and repair costs. This is why vehicles with over 100k miles still fetch a fair amount of money. Computers are very good at doing the same thing over again indefinitely, unlike fully mechanical implementations which tend to drift out of spec slowly over time. A side effect of that is they require more time to actually get in and fix things.
Unlike older cars, the way newer cars work is shielded within software and hardware black boxes and aren't particularly modular. You can't just pull a carburetor out of one car and put it in another. And you're fully dependent on the manufacturer to publish meaningful diagnostic information.
Off the cuff, I'd say at least half of my repair costs are the labor. Any chance you've seen figures on how much more expensive the parts are for newer cars?
It has to do with modularity and commoditization. Modern parts can be highly integrated and digitally customized to specific applications, in such a way that they become increasingly scarce and eventually impossible to find, whereas older cars are mostly made from commodity components where the same part is interchangeably used in tens or hundreds of vehicle models, and many become cheaper and easier to obtain as time goes on and tooling costs are amortized over decades.
Its not just the replacement parts cost. Modern cars are more tightly packed and not designed for individual parts being replaced afterwards. Sometimes its just things like a screw holding something behind the center console being accessible from the engine compartment in a position that forces a full engine/transmission removal. These are tiny things but can turn a 30 minute job into two person days.
Or a oil pipework that cannot be removed from the engine because there is a bracket in the way, which can only be removed by taking out the the master brake cylinder, which requires the brake pedal to be loosened. The brake pedal braket is mounted by 4 screws, one is only accessible by removing the cladding behind the steering wheel, the steering wheel blocks that, so you have to take that off, too.
Based on your comment, I expect newer cars to have lower maintenance and repair costs, fewer part failures, and less guessing about exactly which part is broken.