It's meant to be a Firebase / Supabase alternative.

Yes, you can always build a better backend yourself if you know what you're doing, or you can go from zero to having a proper auth (username/password, 0auth providers, one-time emails, multi-factor) to plug into by running a binary.

Unlike Firebase, you can run it anywhere. Unlike Supabase, you don't need 10+ containers to do so.