The fact you see all porn as degrading is a conservative viewpoint. Even ignoring that, your argument boils down to the same "violent videogames cause children to be violent" nonsense that has been pushed by conservative/religious nuts since the 90s and is thoroughly debunked. Media alone does not shape a person's world view, it at best reinforces existing preconceptions and biases.

I'm not even going to get into the fetish thing, because that's been long used as an excuse to demonise LGBT people and frankly you should know better if you're "progressive".

People who are anti-porn tend to have very sex negative views of the world, close to those you see out of puritanical conservatives. Oh, the language changes, but it's the same narrow minded horseshit used to dictate/control how men/women express/conduct themselves.

A kid seeing a tit ain't going to hurt them, at least no more than the flood of misinformation and violence they are subjected to thanks to other stupid belief systems that permeate western culture.

Not so much good as less harmful than the brain rotting shit people like you force feed them.