I think it’s comical that a group of techies make broad assertions about what’s film able and not film-able. It’s like because we’re smart in one domain then we are smart in other domains and can just make baseless claims not grounded with experience.

If an experienced film creator made such claims then it’s worth listening. Otherwise these sorts of comments are just noise.

My point is that something is only unfilmable up until the point at which someone makes a good film about it.

There's lots of literary attributes which may make a series easier or harder to adapt, but, just like Dune used to be called unfilmable for the heavy monologue, length, and nonverbal components, a director with a vision can overcome them.