How to make the "Pictures" folder a folder again
Using answer space to provide pictures...

Get Info on both your Pictures &amp; Photos Library directories, make sure they are named as below, Pictures &amp; Photos Library.photoslibrary
Also check whether the extension is hidden for only the Library &amp; whether something managed to rename it with a double extension .photoslibrary.photoslibrary - which has been known to happen.



The Pictures directory ought to be protected by SIP &amp; not allow you to change it. Post a comment below if the Pictures naming is wrong &amp; you need to change it.
Photos Library can be renamed at will [though Photos.app may lose it until you tell it where to look]  

To look inside the package, you can just right click it &amp; Show Package Contents, however, the .photoslibrary structure can be toggled between a regular folder &amp; package by adding/removing the .photoslibrary extension then rebooting.

Post a comment if I missed anything &amp; I'll tweak my answer.