Sorry for the loose use of language. Everything that follows the colon after "I believe to be a fact", until the end of that paragraph, is the content of what I believe, including the statememt "It's just a fact." I believe that it's a fact.

Anecdotal evidence: I've interacted with dozens of other people who call themselves web developers over the years, and most of them (outside of Silicon Valley) have never used PostgreSQL, nor any advanced features of SQL in any other RDBMS.

Objective evidence: the large market share of WordPress, Drupal, and other content management systems that don't use any advanced database features; as well as the large market share of frameworks such as Rails, Django, and Laravel that encourage developers to stick with the ORM and not care about advanced database features.

Thanks for clarifying. It does seem all too common to pretend the database is a black box (via ORM) in the most popular frameworks.