The way I like to describe it is that it feels slippery, like it's been polished down to oblivion and my eyes slide right off of it. There's no place to find a mental foothold, and if you zoom in there aren't any details.

But I also like your candy analogy because I think it's spot-on for how LLM text superficially looks informational/nutritious, even though it's actually just junk.