I have been granted Power Apps Admin via PIM, activated it, and can now see more environments when I look at the dataverse tab under the capacity menu (previously I could only see a select few)... so the role has improved that level of access.
However, I need to view the capacity tab to verify our entitlements etc...
According to the documentation Power Platform Admin is all I need - is this correct or do I need Tenant admin access because something isn't working?