I think the 4 throughlines are the key. Do you have em? Which leads to the question: how do you know you have them?....
I think there is a spectrum. Some movies technically have all 4 even though you have to squint and turn your head sideways to see it. You might have one of these "barely there" storyforms. These are not better or worse than the "more widely explored" stories. I only mention it because I often say there is not storyform when in fact there is a "barely there" storyform.
Many of these have an emphasized throughline and in some ways the other throughlines all look directly tied to it even though from a certain perspective they could be distinct. For example, I would call The Fugitive, Spotlight, The Usual Suspects, and Hamlet "tightly intertwined" stories that focus mainly on one throughline while the other throughlines are technically there beyond that throughline's focus--but it's not as obvious to me compared to other stories.
At the other extreme, some stories have really distinct throughlines that are harder to conflate. For example, Michael Clayton, Groundhog Day, Rocky, To Kill a Mockingbird (the book more so than the movie), Witness, Lone Star, Field of Dreams, and Silence of the Lambs. In these stories, it's clearer to me that, for example, Scout's annoyance with Calpurnia is clearly the MC throughline while the trial with Atticus, Tom, and Ewell is the OS, etc.
TL;DR If you can make a case that you have 4 throughlines (the most essential part of a complete story that separates it from a tale), then you probably have a storyform. The rest is for the DUG!