The problem with sexuality studies is they're inherently self selecting. Most people simply won't discuss sexual issues.

Also, I'd invite the authors to wander around the next Folsom and then make the same conclusions.  While I would agree that embracing an open sexuality is healthier emotionally, fetishism, ime, is too strongly correlated with addictive behavior patterns and reinforcing past traumae (good or bad, yes there can be 'good' trauma).