Why am I able to connect to postgres database in aws without 'rds-db:connect' inline policy?

Question

I'm following AWS docs for connecting to an instance of postgresql database that is hosted in my VPC.

• I'm using AWS RDS service configured as Postgresql
• I've configured database authentication to be Password and IAM database authentication

In AWS I have:

• Created inline policy called dbconnect as mentioned here
• Created IAM user db_userx
• Attached policy to the db_userx

In Postgresql through pgAdmin 4:

• Created a user called db_userx
• Assigned them to rds_iam role
• On Privileges 'Can login?' has to be manually enabled (without it user is denied login access)

In .NET 6 code I am generating token to authenticate:

string authToken = RDSAuthTokenGenerator.GenerateAuthToken("...rds.amazonaws.com", 5432, "db_userx");

The database connection is opened successfully. However when I detach the dbconnect policy from db_userx. The user can still open db connection.

Alternatively, when I remove the user from the database and just add the policy, db_userx is denied.

I know I'm missing something here but can't pin point what, anyone has any ideas?