Dune screenwriter works in 30-year-old MS-DOS app, obeying dictat of Butlerian Jihad

Eric Roth, co-writer of the screenplay for blockbuster hit Dune (and how odd it is to write "blockbuster hit Dune"), works using a 30-year-old screenwriting app that runs under MS-DOS, an operating system last updated 21 years ago. He types using a magnificent IBM Model M keyboard of even greater vintage. The app, Movie Master, is long-discontinued but retains some cachet among those who appreciate well-made, focused software.

"Why do you test for humans?" Paul asked the Bene Gesserit crone.
"To set you free."
"Once men turned their thinking over to Windowing Systems in the hope that this would set them free. But that only permitted other men with Windowing Systems to enslave them."
" 'Thou shalt not make a GUI in the likeness of a desktop environment,' " Paul quoted.
She nodded. "We have two chief survivors of those ancient schools: the Bene Gesserit and the Hackers Guild. The Guild, so we think, emphasizes almost pure mathematics. Bene Gesserit performs another function."
"Politics," he said.
"Kull wahad!" the old woman said. She sent a hard glance at Jessica