Active Directory and Local Users logging into the vSphere Client are missing the 'Assign' button for Tags on the summary page
Users are assigned proper vSphere Tagging permissions (below), but the 'Assign' button is still missing upon login
The 'Assign' button is visible for users with global administrative access
This issue is/was not seen while running vCenter 7.0.x
Issue is only seen on vCenter 8.0 GA to 8.0 Update 2 environments
Assign button tag within the UI which gets elevated to true on login was only looking at Global Permissions for users and not taking into account other Inventory Permissions
Upgrade to vCenter 8.0 Update 3 which contains a fix for this issue
Workaround options
1. Right-click on the VM to assign the TAG
OR
2. Give the impacted user(s) Global Administrator Permissions. This option should be given careful consideration as Global Administrator Permissions for a user gives full access