This is a comment I bumped into when reading a review of a book on Goodreads:
The main distinction between characters in this novel is which precise arcane subject they are obsessed with. Is it fonts? Is it miniature practical effects? Ancient architecture? Data visualization? Life extension? In typical nerdbro fashion, people are not interesting for their emotional or psycho-social development (we are left to conclude they have none) but rather for their nerdly obsessions. I have no problem with nerdly obsessions, except that they are a poor substitute for actual character development.
I have no say pro or con about the book in question, which I haven't read, but this mode of characterization is familiar to me from many other things. It feels like something that started with the likes of Thomas Pynchon and later under David Foster Wallace, where a person's vertical, topical obsessions are used as a substitute for actual character.
A lot of stuff aimed at nerdy audiences comes off like this. The implication, I guess, is that by creating characters who have the same nerdy interests as the readers, the readers will automatically identify with the characters, and thus you can save yourself the tedium of actually making them into people, because god knows that's actually a difficult task.
Some time back I wrote a book about people who were defined at least in part by their nerdy interests (The Four-Day Weekend), and it wasn't long after I finished it that I saw the limits of that approach. It's always fun to write something that's a love letter to a scene you enjoy, but I had trouble making the book into more than just that. Even the people I knew who I could charitably describe as fans or nerds about one thing or another had far more to their personalities and worldviews, and a big failing of the book for me was how I'd not conveyed that.
As a result, I set a little rule for myself: I would endeavor, as best I could, to not write about people that resembled myself or my friends in terms of their tastes or their proclivities. This I did as a get-out-of-the-bubble exercise: a way to force myself to find characters on their own terms. I think I was primed for this better than I realized because of the amount of reading I was doing that wasn't related to anything nerdly and that wasn't SF&F generally. (Again: no diss on them, just saying this was how I got out of my bubble a little.)
The writers I got the most out of were the ones who seemed least interested in flattering or cozying up to their audiences. Not the same as treating them uncharitably or brutally, though. Just that they knew better than to make their stories into little more than catalogues of the tastes of their readers.
Other Lives Of The Mind