I do have to say that I had to buy a new vehicle last summer to replace a 13-year old one and the sheer number of sensors, motors, and other features--at least some of which seem rather gratuitous--gave me some pause. And this was a very middle-of-the-road Honda. Certainly a lot of modern vehicles are very reliable although I wonder if they could be even more reliable if, e.g. the side mirrors didn't tilt down every time you backed up.

Do you think these cars get crushed or are bought by someone who drives them until they are really dead?

I hate to be that guy but the whole automotive market has been like that for as long as there has been an automotive market. One person’s unreliable old car they bought new is someone else’s daily driver that they get their cousin to keep on the road for beers.

This really depends on the failure. In the specific case of gasoline direct injection, a motor which has had poor carbon buildup might need to be totally rebuilt. And given the complexity of the motors, it's not like rebuilding an old flathead Ford engine. I'm definitely not saying that old cars are good and new cars are bad. But some of the problems of modern cars make long-term usage costlier and more difficult in some cases. To be clear, cars today are much more reliable than decades ago. I'm just making a small case that this reliability has been sliding backwards in some instances. Some modern cars are less reliable than the same model 10 years ago, and even when the car is not a total wash there are more things that break, and the cost and complexity of repair is higher.

It’s all a matter of trade offs.

Direct injection allows them to do some magical things inside the combustion chamber for efficiency/performance gains with the trade off that the valves are ‘dry’ so will need some maintenance down the line. Maybe you save more on fuel than the cost of having to pop off the head(s) down the line, maybe you don’t. Same with the multitude of sensors, knowing what exactly the engine is doing lets them control it more optimally.

Though I do agree that they add too many unnecessary things like Heated Seats as a Service (looking at you BMW).