Preface: this is no duplicate
This is not a duplicate of this question Which Salesforce License is required to use Dev Hub (beta)?
Dev Hub and Environment Hub are two totally different things. Only the question about which license is required for using each of them can be asked for both distinct Hubs. Please don't get confused. I've carefully split up these two questions and the duplicate mark is definitely wrong.
Today I've tried to enable Environment Hub for some of our Developers. Environment Hub itself is working only for me as I am using a Salesforce license with the Profile System Administrator.
Since the Devs are not involved in selling activities, we use Plattform Licenses (Force.com) for them.
Now they should be able to spin up and manage SSO for our dev orgs.
I was able to grant them access to the tab and the objects - but not for the Environment Hub App.
Is there any way to allow these licenses to use the environment hub? If not, why such an restriction? It does not make sense to provide them with a Sales Cloud License.