So...here's the thing with all this. I think we would probably all agree that this issue is only going to get worse, not better. Government regulation for crash safety, emissions, and fuel economy is unlikely to become LESS strict. Consumer preference for the tech is unlikely to decrease. The cheaper new cars that don't have all the crazy expensive/complicated tech yet will inevitably have it in the future. Consumers want that garbage, it sells.
So I anticipate there being a time in the not so distant future that you're going to be forced onto one of two paths.
Path 1: The never ending treadmill of buying new or new-ish cars.
In this scenario, you act like many people and buy a new-ish car every 3-5 years, keeping up with the times. Financially, this may sound like a good idea, because you're unlikely to have to deal with the servicing issues as the cars age...but you're going to have a perpetual car payment. Also, if you like to modify cars like I do, this route sucks because you sink money into cars and then sell them, realizing a higher loss. I really resist this path from a principled perspective. Spending your whole life with a car payment is a really good way to ensure you don't accumulate much wealth for most middle class people.
Path 2: You buy and hold an older car (or cars) that you can fix.
Like I mentioned above, I think my plan is to assemble a family fleet of vehicles that were in very common use (or use parts-bin parts) in their day, but are from the late 90s or 00s. Things like Pather body Fords, Full Size trucks from the big 3, etc will have parts available for decades and decades because of the sheer volume of production, minimal changes over long life-cycles, and size of the aftermarket. With this approach, when you need a car you go out and you buy the nicest, cleanest, lowest mileage example of an older car that you can afford, and you maintain it with the goal being to keep it as long as you possibly can.
I honestly think that in the next 20 years there is going to be a huge run on the market for 90s/00s cars because I know I'm not the only one who considers them the "sweet spot" in terms of safety, tech, comfort, etc. Just new enough for airbags and fuel injection, just old enough not to have the insane level of tech. I personally would rather start buying up the cars I want from this vintage now while they're cheap and plentiful than wait until their values start climbing and availability tanks.