Node display based on conditional view [NULL] field entry or a Rules expression
you will need flag module make a global user flag: user_has_content, make a rule: react on event: after saving new content of your special type, add a condition: user author is NOT flagged, inside rules action: flag it, only once your user author will be flagged, then on your view, add relationship to author &amp; one more relationship on the new flag on author, and display content if user is flagged, make another view, display whatever you want if user is NOT flagged, this works also on D8, done.

EDIT: since you are using panels, it's easier, make 2 panes as explained, and in panels add this 2 panes, make your rules inside panels UI, display pane 1 if user is flagged, display pane 2 if user is not flagged.