If you like money, then yes! You need to be registered with a PRO (Performing Rights Organization).
We highly suggest that your non-exclusive tracks are registered with a PRO. This ensures you can collect all the royalties you’re entitled to from performances and broadcasts. You can enter the ISWC on all track uploads. Please note, you are responsible for registering these tracks. That Pitch at this time, does not register tracks to performing rights organizations for you.
Registering with a PRO helps you maximize your earnings from your music, so it's definitely worth doing.