You can map the availability of pornography to a rise in risky sex practices like choking. This isn't a problem inherent to pornography itself—rather, it's a factor of inadequate sex ed combined with the commonplace irresponsible presentation of certain sex acts in porn. Still, it'd be misleading to present porn as an entirely neutral depiction of sex. Mainstream pornography demonstrably does spread some harmful ideas. This is also true of Hollywood cinema, though; all media works this way, to a greater or lesser extent.