Just because it's on a touchscreen doesn't mean it has to be tiny and hard to touch. A 17" touchscreen could have fewer controls than the same hardware panel. And the controls could be bigger on the touchscreen.
Imagine trying to find the right switch on this by feel, without hitting the wrong one by accident.
https://live.staticflickr.com/6150/5990351987_fb9c159ea5_b.j...
That said, usually you make a short look at the panel to benefit from that hardcoded visual-motion coordination hw in your head.
This raises a question: how many times do an average pilot actually flip a switch over their carrier?
Worth mentioning that these days GPS units seem to be getting touchscreens but usually still aren't losing the physical buttons.