Format Everything Talent Polygon

As you boot the console, hold L + D-Pad Down + A until you get a message asking you if you really want to delete all your content.
There is also L + D-Pad Down + B to delete the auto-saved content.
Left Button is Yes, Right Button is No.

Just as a warning, if you do that in Talent Studio, the movie with Hiroshi Yamauchi's message will be deleted.

Confirmed to work on Talent Studio and Polygon Studio.