I see no particular reason to believe that Postgraphile, while a good tool, is any better (or any worse) than PostgREST, just as I see no reason to believe GraphQL is better than REST.
As for layers of abstraction, one can have layers of abstraction with PostgREST: views and procedures.
It's not better because it's gql, it's better because it's more feature complete (like RLS), offers more/easier customization, isn't written in Haskell, etc., but ofc your milage may vary.
> As for layers of abstraction, one can have layers of abstraction with PostgREST: views and procedures.
I can't even imagine a more closely coupled and leaky abstraction than views and procedures in a database
The database has RLS, and I don't care what PostgREST and Postgraphile are implemented in, so personally I'm unmoved by these two claims.
As for things we're unable to imagine, what I can't imagine is how table structure (for example) could possibly leak through a view or procedure. You're welcome to try to explain it, though you're not obliged to.
As for layers of abstraction, one can have layers of abstraction with PostgREST: views and procedures.