>Rails developers at the time who were largely encouraged to treat their database as a dumb data store by convention and to let the application do the work
I've worked in a big enterprise once (hated it for all sorts of reasons) where the business logic was entirely in the database, I get that that could work too. But in the sort of environments where I've worked most, there's a lot of knowledge about the application programming language, and less about the database. No dedicated DBAs. And we all know our SQL, we build basic NOT NULL and foreign key contraints, maybe a simple uniqueness constraint in SQL, but otherwise concentrate all the application logic in... you know, the application. For better or worse, I guess it's a coping mechanism for application developers. (And then it becomes a habit, maybe for some, like the article said, dogma.)
I've worked in a big enterprise once (hated it for all sorts of reasons) where the business logic was entirely in the database, I get that that could work too. But in the sort of environments where I've worked most, there's a lot of knowledge about the application programming language, and less about the database. No dedicated DBAs. And we all know our SQL, we build basic NOT NULL and foreign key contraints, maybe a simple uniqueness constraint in SQL, but otherwise concentrate all the application logic in... you know, the application. For better or worse, I guess it's a coping mechanism for application developers. (And then it becomes a habit, maybe for some, like the article said, dogma.)