why can't they keep the original factory button when they design these systems?
Cost, its cheaper to create a software button.
With the vf the buttons are connected to the screen and the screen contains the programming for them so to retain the oem buttons they would need to reverse engineer the the button modules and design an interface for them to connect to the aftermarket unit.
That all costs more so a simple touchscreen and a software button is the most cost effective option.
Buttons in vehicles will become a thing of the past soon with the entire dash becoming a touchscreen, you see it more and more in newer vehicles.
Its all cheaper but it is going to be a pain in the ass for the consumer when things break, lagg, crash or freeze.
Be like having windows 98 in your vehicle lol