@mxoh I believe I truly understand your question as I'm in a similar position as I'm also trying to figure some things out with setting up Dropbox for Business with AD.
Although, this question was marked as solved, it doesn't really give the answer as it was probably given to you via direct email. On this post however, everyone that tried to help from Dropbox didn't understand your question. I'm posting this for the benefit of those like me that didn't get that confirmation via a direct email.
I found this article on Microsoft that explains it easily that yes Azure AD does support both users and groups:
https://docs.microsoft.com/en-us/azure/active-directory/saas-apps/dropboxforbusiness-provisioning-tu...
The one thing I'm still hung up on is finding out if both AD Connector is needed or just Azure AD, because from everything I've read it seems there is an older way that's not going to be available as mentioned in the article and a new one via Azure AD. So, for the provisioning of users and groups and using SSO it seems Azure AD works for that without using AD Connector.
From what I'm understanding and please correct me if I'm wrong anyone, the AD Connector says it's only used if we wish to sync groups not just users, but yet Azure AD says it can do both...this is where I'm stuck but I will be testing this soon and I'll eventually get my answer if I don't find it online first 🙂
