I think the biggest change is that it's more available to anyone, you don't have to struggle to find porn online and to download it, so while girls expect their life like in soap operas and love movies, the boys expect their intimate life to be like in porn. There is nothing to explain, this is instinct, people love having sex and try different interesting things, so that's why porn is so viewed, cause there are fantasies in there that are harder to fulfill in real life, like positions and thematics. So, everything I wanna say, is that you need to impress your partners with something cool in bed. I can suggest you to take a look at
pornid, there are many vids with girls that can do magic.