Row level security is for customer tenancy. But how do you implement user based tenancy for a particular customer ? I reckon, you need here something like column level security here ?

https://www.thenile.dev/blog/multi-tenant-rls

SET app.current_app_user = 'usr_123' and SELECT current_settings('app.current_app_user)

is one way to do it. not sure what you would need column level security for. what are you wanting to filter?