This may be a regional thing. I've seen Drupal 6/7 on a lot of sites where the original dev threw together five content types in the admin GUI and told the admin how to post new content. It worked well and was certainly less worrisome than seeing (outdated) WordPress.
So your argument is that a multisite project running a thousand sites off the same codebase containing custom forms and layouts is simplistic? Then, I pray, what do you call complex?
That's not a sentence I expected to see. Ever. Drupal is popular for many things but for simplistic sites?