Supabase at is minimum providing a PostgreSQL server, pooler (they started on pgbouncer, how their own) and a PostREST API, and support, backup, logging etc. You can be doing serious business and not have the time/people to run these reliably self-hosted.
They also provide Auth almost to the Auth0 level and Edge functions like Vercel, S3 like storage (sharing the db's permission system), and websocket/presence backed by Elixir. TBH they are a compelling value, at least for us.
Granted, Supabase does provide a lot under the hood, and it's excellent for whipping out a quick MVP, but I wouldn't count it production ready even today, simply because of the downtime I've experienced at times (even if their dashboards say otherwise). And it's not just an isolated case - a lot of folks on reddit complain with the same issues. Perhaps your treatment is different because of the high spend you guys have.
