If you want the timestamp/Date column displayed as 'YYYY', you need to change the setting I posted before in Preferences->Advanced->Tweaks, viz:
You may have to scroll Preferences windows to get to Advanced. Search for 'date'
You can only add or change
Custom columns in Preferences->Add your own columns - e.g. the ones in the red box, viz:
The built-in columns are in that list so you can a) include/exclude Book List columns and b) order the Book List columns.
BR