I think you are right, and I've at times struggled to explain why I enjoy his books as much as I do. I think ultimately he leans regularly on a facet of SF that in that genre, ideas and abstractions can be the equal subjects of character development. Cleverly developing an idea (e.g. mind virii) and circling back on those ideas, exploring how different facets connect in different ways, is the kind of thing one does with a human character, but can also do with an "idea character" in SF.

Obviously the craft and virtue of that kind of thing is in the relationships of the concept to other elements of the tale, both human and non-human. This I think Stephenson does very well, but I can appreciate that for someone who doesn't extend subjectivity largesse to abstractions, it can be tedious to read wikipedia-like explositions, no matter how well done. :-)