From all my reading in the Drupal subreddit, modern Drupal isn't especially useful for real world scenarios without a bunch of contributed modules and stuff... hence Drupal CMS. Additionally, folks were recommending not using Drupal 11 until it had been out for well more than a year due to the sad state of contributed module upgrades. I'd wager this is due to the much smaller Drupal community than the version 7 highs.