Back a few years ago when I used to program and troubleshoot PLCs, a touch screen laptop would have been very nice to have as motor control centers and other locations PLCs are found tend to not have a lot of space where a mouse is able to be used. Unfortunately touch screen laptops did not exist at that time. Today I'm happily retired and somebody else gets to wear beesuits in MCCs while trying to figure out what (if anything - 99.99% of the time it is a broken switch, loose wire, or bad sensor) is wrong with the PLC.
Therefore I see no use for touchscreen. Except for Windoze 8, i f the rock it crawled out from under can't be found and it get re-buried. Guess Widoze 8 is Micro$oft's tribute to zombies!