Microsoft will disable Basic Authentication for newly created tenants by default and begin to disable Basic Authentication in tenants that have no recorded usage starting October 2020. For those tenants still actively using it, Microsoft will begin to disable Basic Authentication in tenants the second half of 2021.
An enhancement request (#32403) has been created.
Enhancement request #32403 has been implemented in version 8.1.3. A hotfix might be available for earlier versions (8.1.2).