Touchscreens work well with a Menu-Only system - a system that has a very finite number of options. Cafes and restaurants do this well.
But in my retail world, our touchscreens are seldom used because typing is needed on at least some sales, so our staff is more comfortable using the keyboard, even if it’s merely to tap ENTER. This is an easy touch-screen process, too, but no one likes the fingerprints on the screen. On restaurant systems, those are even more visible. Kinda yucky, too, in a food-biz industry with health concerns.
Touchscreens aren’t new, though. The limitations for those back in the late '90s are still there - the application and user productivity are the key issues. Not the OS, not the hardware. Using Touch on my smartphone, it’s a pain to scroll thru ‘pages’ and changing websites is far more difficult because of the keyboard limitations. That all changes on a computer - but not a tablet - because of the easier keyboard functions.