Its default state in not enabled. I do not think is posible to trigger an event when Photoshop is closing down but you can wheb Photoshop start up. So if the Script event manager is enabled when you close Photoshop you could triger an application start event when photoshop starts that may be able to un check enable the script events manager.
You want to turn them all off?
Delete this file on quit: (similar one for user on mac) Not sure if you can get the quit event and actually do anything...because we are quitting but you could try adding a script that does this on
|#define eventQuit||'quit'||// kAEQuitApplication|
C:\Users\<user>\AppData\Roaming\Adobe\Adobe Photoshop CC 2015\Adobe Photoshop CC 2015 Settings\tw0001.dat