But “open source” doesn’t even mean that you can reproduce it or use it for free.
You’re thinking of source-available licenses. Open source has a clear and widely accepted definition that requires a certain level of freedom. You’re free to ignore this definition, but you can’t expect the rest of the world to do the same.
To be clear, open source allows for only providing access to paying customers, but those paying customers are then free to use and distribute their copies without any further payment. Then it wouldn’t be open source anymore.