"Reinstall" schema registry, to reset all subjects

[th0ger]

We are running a pilot in schema registry and want to clean up all schemas.
No messages in kafka are serialized with respect to the registry (with schema_id in their header/value).

Soft and hard delete has been applied on all subjects, but _schemas transaction history is very cluttered.

There is no "uninstall" guide for the registry afaik.

Is it safe to or delete the _subjects topic?
Is it even possible? (It's an internal topic.)
Will it be recreated automatically by the schema registry service with the correct properties?