We humans just like good engaging stories, even if they are not always realistic.
Even deep space maneuvers can be done manually if you know what you are doing - point ship engines in right direction and thrust for right number of seconds/minutes.
Sure, for stuff like orbital launch, some crazier Oberth effect burns or continuous thrust propulsion (ion, solar sail) you definitely want computer control.
I can see an argument for manual landing on another cosmic body, given the famous story of Neil Armstrong saving Apollo 11 landing by manually landing the capsule. Though the latest generation of lunar landers can perform the procedure fully autonomously, using machine vision to find an optimal landing spot.
I tried looking up, whether manual or automated moon landing is planned for HLS program, but couldn't find anything specific. It's probably going to be some mix of both.
Or they imagined that such devices would be much more powerful but much less general than what we actually have. The card showing books being shredded and fed into students by headphone looks like a computer to me even though it is cranked manually. Quite a lot of my software development career was dedicated to programs that transformed knowledge in one form (specifications and domain expertise) into knowledge in a different form (detailed drawings, bills of materials, and descriptions of the final product.
People in Matrix movies were not doing much.
Perhaps this hints that our vision of the future should have us doing less.