It can, indeed, encourage and support pedophilia. We're coming to a point and time where the Internet, and the accessibility to NSFW content, can shape people's sexual tastes. Which isn't always a bad thing, but with underage NSFW, it is. If people see underage NSFW content from the time they're young, it can follow them through to adulthood; they don't disseminate why it's wrong to sexualize an underage person.
Sexualizing an underage person is, plainly, pedophilia.
Media influences us, even when we don't realize it and affects thought processes. Sexualizing underage bodies affects other things, like dress codes that target girls for wearing shorts or marginalizing/gaslighting teenage boys victimized by adult teachers by saying the boys enjoyed it. Sexualizing teenagers is so commonplace, it's shown in shows (Family Guy, tons of schoolgirl anime, etc,) in advertisements, in Halloween costumes, and in people who indulge in "countdown until they're 18" timers for their favorite child celebrity.
Your kitchen knives comparison is a stretch; knives have other purposes they're sold for, where as NSFW content is specifically for sexualization.
Equating BDSM to rape is just a bad take; consent is hugely important in any kink lifestyle.
This is derailing the rest of the thread, though, so I won't continue this with you here. I only added it in my previous post as an example, to illustrate deeper comprehension of a stance, since a lot of people look at it superficially.