That could be because filmmakers didn't know about their existence. SciFi predicts a lot but also borrows from current knowledge; for example, we've seen black holes depicted in different ways according to the knowledge of the time of the writing/filming. Also, for many years before touch screens became reality the only known direct interaction with a screen was like a light pen, whose operation was slow and clumsy (can't "push" more than a "button" at the same time, wires, etc) which could have discouraged the idea suggesting to wait until the idea of operating screens directly using hands was conceived and became popular; probably in ST TNG LCARS interface.

https://www.cygnus-x1.net/links/lcars/epics/TNG-S4/S4E3/TNG-...