you are mixing topics. In your world, a phone Must be supported by original vendor, no one else can support it. THIS IS ONLY YOUR NARROW OPINION.
If Apple cannot support these old phones, fine. Then open the app markets to allow customer support themselves.
It’s my phone, I paid the full price on that phone. Maybe it is too old for modern app, but I can still use it as dashcam, IFTTT Gadget or alarm sensor. By keeping app market locked and not allow new app to support old iOS, Apple is forcing user to throw away their phones.