I wonder if prints of it still exist in a vault somewhere.
Peter Hyams essentially made 2010 much more along the "Clarkeian" lines suggested by Moorcock in the article, but even still some of the talky bits around Bowman's various appearances did not make it into the final cut.
It's a good enough film, but you would be hard pressed to find anyone who honestly prefers it to 2001, or who thinks adding in more talky bits would have helped. Indeed, compare the Soviet vs American "stand-offs" in the hotel lobby and in orbit around Jupiter respectively, and you can see Kubrick's subtle treatment of the cold war as a much more savage commentary on geopolitics than the overt on-the-verge-of-hot-war geopolitics in 2010. The climax of 2001 was the result of the cold war paranoia, whereas the climax of 2010 were events that overturn the less-cold war paranoia of the sequel.
2001's Kubrick-ness is reflected in that sort of subtle political satire that was one of the recurring themes in his films; Clarke by contrast favours an optimism based in technological leaps, which we see in full in 2010, but also in the novelization's elucidation of the film's ending.
Maybe the most famous transition in film history -- the bone thrown into the air -- exemplifies the difference: Kubrick takes a "you can take a violent ape out of the savannah and dress it up in business clothes, uniforms and space suits, but..." view while Clarke thinks the new environment transforms humans for the better.
As you say, it would be fascinating to have fuller documentation of the film-making processes for 2001, to at least the level of detail that we get for major films made in this millennium so far. However, as with 2001 itself, we have a large vacuum to speculate about.
It still wouldn’t be 2001; in has the bones of a very different film. But as a rare example of a hard SF movie with a terrific cast and largely excellent writing, it could certainly stand on its own.
To me, the universe of 2010 was just barely within stretching distance for society in some forseeable future, whereas Star Wars and Star Trek were unreachable. That somehow increased its appeal to me as a child, as I could envision living in the world of 2010 in a way I could not with other sci-fi universes. The universe of 2010 was my universe, in other words.
I've been afraid to rewatch 2010 as an adult, because I know I will see it differently.
The hot dog scene by itself is a classic bit of screenwriting.