Writers Steven Lisberger and Bonnie MacBird had a great visionary story, and as a director Steven knew how to bring his imagination to life through cgi. What Steven didn't know was how to communicate his ideas to experienced, solid actors.
Lisberger did his best (see the disc Extras), working on blank sets that wouldn't be filled in by cgi for another year, but his actors couldn't uniformly agree on what that world they needed to interact with would look like, and Steven couldn't communicate it any better.
Everything we see within the computer world of TRON is what the actors couldn't see.
The movie suffers for it, both in the different actors muddled reactions to the same thing, as well as some horribly awkward dialog, so out of place with the events happening to the character.
Our modern superhero / comic book cinema era was grandly laid out for generations before it reached this blockbuster point, and there was tons of missteps throughout the decades. Few remember that Marvel didn't get solidly on its feet until 2008.
Like Star Wars, TRON laid the groundwork for everything that would come after and build upon it. Unlike Star Wars, the actors were as out of their depth with the story as the director was out of his in directing it. What likely helped Star Wars was all if its practical effects, giving the actors Some Thing to work with.
A young Tim Burton wanted to direct TRON as his first feature, and Steven was happy to let him have at it (see the disc Extras), but a bad short film Tim made with live actors at the time gave the Disney bosses cold feet.
So what does all of this ancient triva mean for the viewer? Is TRON entertaining or not?
It's quite entertaining as the world Steve created back in the late 70s, early 80s is in many ways more compelling than cgi worlds we have today. It looks now like a computer savvy person of this era would expect a computerized world to look. By comparison TRON: Legacy was one note and while written better, drew upon shallow, ugly-hearted characters that no one could care about.
Unlike Legacy, Steve didn't want his computer world to look like a realistic version of earth, which would have been easy enough at the time with mere neon and light panels.
TRON takes us fully into an imaginary world, far more fantastic than Alice's Wonderland – even if the computer characters all talk like they just stepped off the set of Bonanza.
TRON remains a rich landscape, flawed yet beautiful, worth repeated visits, and the extras are great!