In practice it’s an absolutely stupid design. If you create tables without using their dashboard, like with an ORM or with SQL directly, it’s incredibly easy to have them not use RLS and be wide open to the public.
Taking a step back, the whole “query the database straight from the frontend” is a terrible design in general. For example, they still don’t offer rate limiting! Even if the tables data is secured, there’s nothing stopping someone from hammering the database directly with reads/writes until it overloads it, as there’s no application level rate limiting in the middle. Bonkers.
Somehow it's okay to simultaneously set a golden path to less secure software to support your hockey stick growth model and then turn around and blame end users when it all goes wrong.