not sure if you are sincerely asking but I'm gonna answer your question sincerely anyway
CW porn, kink
gooning is fetishising one's own addiction to porn. masturbating for hours on end to achieve a hypnotic state of mind-numbing horniness. so basically edging but often with an added humiliation kink - it's become a common theme in femdom clips and hypno porn
why is it bad: addiction to porn and masturbation can get in the way of achieving one's goals or having meaningful relationships with people in the real world. also there is a lot of overlap with other problematic porn genres such as fetishization of trans women and racial fetishization etc.