According to this online report, I guess all 'the old people over 60' are busy buying stuff with their iPhones while the 'youngsters' just play with their toys (Nexus at al) ;-)
They could have 3D Touch on the right side to go back to the home screen (like you left tap for the app switcher).
Assistive Touch is under the accessibility settings for a reason. It's not there for everyone to use instead of the home button, it's for making certain things easier for those who can't use their hands very well - Can't use the buttons, can't do certain gestures, shake the device, or even double tap.
It even has a specific 3D Touch button now.
I had to set my touch sensitivity to light, and I'm still having problems not making my apps change to wiggle/delete mode.
Would it be possible to navigate the same entire phone without hitting the home button once? Would it make sense? I think 3D Touch makes it possible, but not sure.
There are ways you can get close. Accessibility lets you do a lot.
One aspect that I always have to consider is using the Home button for forced resets or force close misbehaving apps/functions. Haven't seen a way around those yet.