Disabling the administrator login on the Developer Portal login page is a user interface configuration that removes the visible link for administrative access. This is often done to present a cleaner interface for API consumers. However, the underlying administrative login functionality is not removed. Administrators can still access the login page by navigating directly to a specific URL. The correct URL for this purpose is https:///user/login?registryurl=/admin, which bypasses the standard login page and presents the administrator-specific login prompt.

1. IBM API Connect v10.x Documentation

"Logging in as an administrator". This official documentation explicitly states: "If the administrator login link has been disabled on the Developer Portal login page

you can still log in as an administrator by navigating to the administrator login page... The URL for the administrator login page is https:///user/login?registryurl=/admin". (URL: https://www.ibm.com/docs/en/api-connect/10.0.5.x?topic=portal-logging-in-as-administrator)