Supabase developer here. "Wrapper" is an oversimplification, but essentially, we provide additional value to the existing OSS offerings (i.e. PostgreSQL, GoTrue, Kong, Postgrest) by adding libraries and server configurations that tie everything together and make it much easier to develop an application. That being said, you're free to self-host Supabase and get all this value (and continued value and support) for free. We only "monetize" it by offering a hosted version as an option for people who would rather not spend time managing servers and other infrastructure.
In addition, the value we add to these existing tools is turned back to the community and can be used however people see fit.
Hope my question didn't come off the wrong way, and really appreciate your reply.
Another question, so does Supabase open source 100% of the added features/functionality? Or are some features/functionality gated behind a paid license?
No problem -- it's a very valid question and deserves to be clear to everyone.
Supabase open-sources everything and nothing is behind a paid license, except for any stuff related to us providing the hosted stuff. For instance, our internal software we created for billing customers who host with is not necessarily open-source.
In addition, the value we add to these existing tools is turned back to the community and can be used however people see fit.