I got an obvious and logical understanding - that he can't show everything and everything doesn't need to be shown for various reasons, respectively - but not a deep understanding. There's nothing under the surface here.
And you got the specific reasons. You keep leaving that part out. Your paraphrase notwithstanding, we're not discussing a general statement. It's a specific statement that in this case, this particular reason led to the artistic choice.

Now, can I read some things under the surface based on it? Sure, but that would be me applying my interpretations and insights (or you applying yours) rather than the Giant giving me his.
That's a feature, not a bug. If the index is just to present complete and finished statements by the Giant that provide some arbitrarily selected level of "insight," I'd like to know that so I can stop dedicating time to it. But its purpose isn't limited to that. But as of now, at least, it's "meant primarily to provide easy access to direct statements from the author for the purpose of forum discussion." If that's not the case, the rules should be updated to reflect it.

And that purpose is greatly served by a collection of specific statements by the Giant about why he made particular artistic choices in particular instances. It allows for discussion that goes far beyond "This comic meant X" and "Nuh uh! It meant Y!"

It's a very common means of analysis to gather multiple situations, each with seeming simple meaning, and combine them to gain a deeper understanding. The fact that we know the Giant shows horrific scenes in some cases, but chose not to do so here, gives us additional knowledge about how he creates.

This is a very common mode of analysis. It's used in literary criticism, legal reasoning, and throughout the social sciences (to generate the ideas that can then be experimentally tested). There's no reason to artificially limit the scope of the index to exclude this means of analysis from the discussions the index is meant to support.

It's the combination of these so-called "surface" insights that allow discussion that goes beyond the typical speculation or clarification debates. Each time we exclude one because it, on its own, doesn't provide deep insight, we make it harder to use the index to discover the truly deep insights that would make discussions on here so much more interesting.