Non-unique tags

I’m using the free version of WPDM. When I look at the tags for the downloads it lists all of my post tags. If I add one here that new tag appears in the generic posts tag list. Should it not be separate?

The link for tags in wpdm is wp-admin/edit-tags.php?taxonomy=post_tag&post_type=wpdmpro so I don’t understand why it’s not unique..