It does work - the basic Fpolicy can (at least could in previous DOT version) do what you're describing - block a file type by extention. Third party tools are required when you need to go beyond the basic file extention exclusions and do content review.
Here's an example that I used (maybe DOT7.2.x) - use at your own risk....
fpolicycreate mp3blocker screen
fpolicyext inc add mp3 blocker mp3(,mp4,avi,mpeg)
fpolicyoptions mp3blocker required on
fpolicymonitor set mp3blocker –p cifs,nfs create,rename
fpolicyenable mp3blocker –f
fpolicyvol inc (exc) add mp3blocker vol0,vol1,vol2