In version 13 I have a shortcut on the Home Dashboard to DocType Account. It is set to open in the tree view.
I set up a new server using version 14 for a new company and when creating the same shortcut, the tree view option is missing. I have to open it in list view, then switch to tree view…
As per the scenario, I checked the workspace shortcut and found the issue.
You are right, When selecting Tree structures related doctype then does not show the Tree option.