My understanding is that the released game was not a "descendant" of that 2001 preview. The game was totally scrapped and then a new iteration was started years later which is what eventually was released. So it's not like the game was actually being worked on for a decade. More like the released game (which was only built over a couple of years) had the same name as a scrapped game from a decade prior.
I was merely framing it that the 2001 build was seemingly on the road to being a good, or at least faithful Duke Nukem game but management kept dictating changes to it to keep up with gaming fads. Eventually Gearbox just shoved an entirely different build out the door.
The 2001 build was victim to a lot of start-stop-start-stop development.