> ...what happens 40 years in the future, when our phones don't run the app anymore...

40 years? How about, like, 3 to 5 years? Remember when Apple decided to kill all 32-bit iOS apps for new hardware? I have an old iPod and iPhone 4S with "landlocked" software I enjoy using but can't anymore because Apple.

Phone manufacturers have shown they don't give a damn about allowing old software to function. Physical devices tied to software is a terrible idea.

Fully agree. We may have to keep a 40 year old phone around in order to just use a 40 year old car's companion app.