How to reproduce:

1. Add a file to the Assets Library, when it has this message shown:

2. After that add a new empty folder also to the Assets Library. The library should look something like this:

3. Delete the "images" folder

After that, the Assets Library shows again the "Looks like you don't have any assets yet" -message. even though there is a empty folder still in there. It would be more user friendly, if the message only appears, when the Assets Library is fully empty.