And the studies that found the so called "benefits of masturbation" were all inconclusive and just a coincidence because of the small sample group. Later, more recent and more thorough studies have found that there aren't any benefits in masturbating.
But, the adverse affects of masturbation is real. The excessive viewing of pornography will cause biases and misconceptions in teenagers especially. And because of the endorphins release, people do it more and more, causing it to spiral and become a significant issue in ones life.