we are facing the same problem as this post:
https://community.esri.com/t5/arcgis-enterprise-portal-questions/why-do-i-need-a-license-manager-for-portal-user/m-p/1299836
However, it was marked as resolved, but I feel that it leaves open questions and installing a license manager is not a good solution (as it was not required before).
Situation:
We license our Pro instances from AGOL and have not needed a License Manager for our 10.9.1 and 10.8.0 enterprise and portal deployments before.
It appears something has changed this year with obtaining a json file for portal licensing.
@MarleyGeddes Creator is not an option, only Viewer or GIS Professional Advanced, this is on step 2, and attempting to select neither fails.
If we select GIS Professional Advanced licenses, we are forced to select a license manager, and port and MAC address/cloud ID.
It doesn't seem like installing a License Manager should be the solution, as it hasn't been required before.