> Is Ford required to repair my car indefinitely..?

Never. But it would be wrong for Ford to stop others to fix your car by providing no information about the car, which I believe is what Microsoft is doing with their obsolete Software pieces (including OS).

As that is the case here, They (Microsoft/Ford) are just lending you something, you won't ever own it. Would you agree with that?

software is not subject to entropy...

The car analogy a very poor one. Software doesn't wear out-- physical stuff does. Defects in software are present when it's created. It doesn't "age" or "break down".

(I am making no comment on the issue being discussed-- simply that this is a very poor analogy.)

Nearly all complex software will have problems and weaknesses not known at creation, much like nearly every car will have some kind of weakness that will wear out. While there are differences between the physical world and the digital one, I think my critique of the concept of demanding infinite warranties is still valid.

And yes, I do think software can "wear out", not in the same sense as belts get worn and spark plugs physically wear away, but in the sense of threat landscapes changing over time and our understanding of how these systems are used in the world. This is why we do maintenance on our software and systems, much like we perform maintenance on things in our physical world. When you fail to perform this maintenance, bad things happen. Computers get hacked, cars have brakes fail.

Software can indeed age. Go run Windows 95 on the public internet or an early version of Android.

I think the car analogy isn't that bad. New classes of security issues get discovered over time. Development processes which are considered "state of the art" at one point can become unacceptable 10 years down the road.

A decade in software engineering is a significant amount of time!

For the car analogy, what will happen when self-driving cars become the norm and the contained software becomes so important?

I'm going to be annoyed if my car becomes useless after 10 years because they dont have to patch it after that period. On the other hand though, can we realistically enforce lifetime guarantees? What is a car company goes out of business?

Pretty sure the endgame for self-driving cars is pretty much nobody owning cars anymore. It will become too convenient and cheap to rent one instead (possibly not in rural areas, not sure about that). Kind of like how very few people in big cities bother with owning cars.

As opposed to others, I would like to agree with you. One can make design decisions which allow for maintenance over a very long, or indefinite period. This would require using formal methods and a different hardware architecture. Unfortunately, in today's world, we are stuck with mantras like "move fast and break things", which entails running away from, instead of fixing, the complexity we leave behind.

> Software doesn't wear out

Software does wear out. New languages/frameworks are developed which makes it difficult to patch older stuff. New threats are developed, and it may be impossible to patch older stuff.