This is probably going to be a controversial post. It's my own gut feeling and is probably based more off my own vague impressions rather than any tangible evidence. I fully expect there are plenty of ppl who would disagree. But, as you asked me to expand ...
Well, there isn't really any one particular part of the documentary that I'd point to for that, for me it's more just my general weariness with the rise of the academic, and I'd probably even go so far as to the pretentious, side of text adventure development.
I understand why the devs who were working on commercial titles back in the 80s use the term - they obviously thought that "interactive fiction", a term coined from the culture at Infocom I believe, was potentially a revolutionary new medium and that they were breaking real new ground for something which might potentially become mainstream and possibly even challenge the dominance of books and/or magazines. I think the AI required to reach that level of adoption will elude us for a lot, lot longer - but that probably wasn't as clear in 1983!
However, reaching towards the modern day, I'm just very tired of seeing and reading people discuss in intricate detail the artform, the medium, what makes a good game, and what doesn't, how characters should be developed, when you need pacing, when you don't. It's all so tediously academic. I don't enjoy reading technical papers in my spare time. Of course, I won't dispute there's a need at all for such discussions - I just think that they have long since come to dominate the main scene to the exclusion of what I actually enjoy - playing the games. I think an extension of my thoughts on this is probably the main reason why I prefer I6 than the natural language approach begun with I7. I don't think you can bring in a traditional author to write such games, without teaching them to become a programmer and, in which case, I'd far prefer the style of I6 than the faux, unnatural English as represented by I7.
In all, "interactive fiction" has come to me to represent everything that isn't fun - which is why I think I intend to try to fall back to "text adventures" as being in my preferred vernacular, as it evokes something which actually reminds me of the games I've enjoyed playing as opposed to IF which makes me think of reading academic papers and seemingly endless r.a.i-f threads. This documentary did tend in places to slip into that IF world - mainly because tha's how the most active people on the scene think: it's considered a very
But, as The Mad Hatter used to say, each to their own; you pays yer money and you takes yer choice - I certainly wouldn't want anyone to take this post as me disparaging anyone or anything - the Inform language itself is a work of art, and if that's the direction Graham et al want to take it, then fair play to them. Though I'm glad they open-sourced I6 before they started off in that direction.