I get it--or maybe I don't deeply get it-- but I don't really find this a huge concern for most web apps. If I know that my app is never not going to have a db

I get it--or maybe I don't deeply get it-- but I don't really find this a huge concern for most web apps. If I know that my app is never not going to have a db, then what is that extra step of that decoupling buying me? I still have fast tests due to transactional rollbacks, and I can even perform certain business logic in the db nicely with Ecto when it's a better fit than the BEAM.