I'll oversimplify video production to make the point, but let's say I'm making a video where a Bob runs up to Alice, makes a snide comment, Alice makes a clever comeback, and Bob slinks away in shame. There are a few creative parts to this:

1) Writing the script.

2) Designing the visual look of Bob and Alice.

3) Designing the animation (e.g. animating the body language of "slinking").

Those are all creative contributions. A tool like this one converts an image into bones, which I don't think has a creative element. It also has a bunch of pre-baked animations of those bones, which are neat, and do have a creative element.

Is that enough? I don't know.

Let's take this to an extreme. In the early '00s, there was a popular video (an early meme) of a pair of stick figures having a rather fancy fight. Most of the work was in the rather comedic body language. If I replaced those stick figures with something my child drew, it'd still be /mostly/ the original work. Simply replacing a stick figure with a child's drawing doesn't change the underlying work. Even if I took a little clip, say a neat-looking jump turning kick, I couldn't take that without permission.

There's a line somewhere in there, and I'm not quite sure where it is. I don't think anyone really knows until there's case law.