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 It worked well and was certainly less worrisome than seeing (outdated) WordPress.

We run about 1,000 simple websites off the same Drupal codebase. Custom forms, page layouts, etc.

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?

Maintaining 1000 servers