After re-watching the TMP Director's Edition with the commentary, I would have to revise my earlier statement to say more accurately that the fault lie with both Wise and Trumbull, with regard to the starship porn cuts, etc. Even Wise saw the need for reducing some of the scenes to run shorter. He said so, for crying out loud!
If there's any "fault" to be assigned, it's with the distributors who insisted on an inflexible release date and therefore forced Wise to deliver an unfinished rough cut to theaters. The cut we saw included all the FX footage only because they hadn't had time to trim it down yet, to make all the editorial decisions about how much of it would best serve the film's overall pacing. Again, you're completely wrong to accuse the filmmakers of making bad or inept decisions. They weren't allowed
to make the editorial decisions they wanted to make, because they were forced to deliver the film before it was ready. It was the only film in Wise's entire career that was released to theaters in a form he wasn't satisfied with. He even tried to convince the studio to let him finish editing the film properly and send out a final cut to replace the rough cut while it was still in theaters, but they refused to cough up the money to let him get the film right. He had to wait 22 years for the opportunity to complete the film.
And as for those other examples, I have yet to speak with any classic film fan who complains about the pacing of TMP, who also complains about the pacing of those other films you cite - especially 2001!
I think the pacing of TMP is fine, whereas 2001
is a crashing bore. Although that's probably because the slow parts of TMP have great music to listen to, while a lot of 2001
is just tedious silence. I've never liked the way Kubrick dealt with music.