You can now create it seems more than one Workspace. By clicking on upgrade and subscribing to another cloud business (don't use this route though if you want another license for another work-space)
But this work-space is completely independent. So you have to pay again if you want to share with a user that already has a license. Including for yourself.
So if someone has information to share in-house with team members one work-space could be used. But if they also want to share to three associated businesses requiring three more streams (or people in other divisions etc) another one could be set up. But you would need two licenses for yourself. But with this you would buy another 500GBs of cloud storage.
I can sort of see the reason why Qlik has gone down this route but would also prefer the option of unlimited (or more) streams. And buying more cloud storage if required.