There is plenty of documentation that what we view influences our attitudes, but it’s not the only influence. Objectification of women and rape certainly didn’t have it’s onset with the ubiquitous availability of porn.
There has been a lot written by those who would know, like Jenna Jameson, that porn actresses are often subjected to discomfort and sometimes outright pain, and then have to pretend that they enjoy it. In the face of the shocking lack of real sex education, some people then grow up believing that this made-for-entertainment purposes stuff is what real sex is or should be like. Since porn isn’t going away, it seems like the prudent thing to do would be to have on-going, real, frank, conversations with both boys and girls starting at a young age about what healthy, respectful, mutually enjoyable sexual interactions are made of.