With Adobe IDs, the user actually owns the login. You as an administrator can remove their login's access from your products but you as the enterprise don't actually own the user. With Enterprise ID or Federated ID, you as the enterprise own the login. You have more control over their login as a result. Typically, we see customers use Enterprise IDs or Federated IDs for their employees and Adobe IDs for third party consultants.
Using Enterprise IDs allows you to also build out integrations with your LDAP server and setup more secure sign in options like SSO with an identity provider.
This isn’t a silly question at all. You can still transfer dashboards,reports etc all of these functions are still in analytics. All we are doing is moving your users and the groups to the cloud. Adobe is vs. Enterprise Ids come down to do you need full control of who accessed your data?