Having a law saying children shouldn't view pornography isn't abuse. It's common sense. Just like saying a 12 year old can't legally buy weed. Is that a slippery slope? Should 12 year olds be able to buy weed? If not, why is that not a slippery slope and this is?
What needs to be kept in check is the scope. Let's say they try to age restrict sites that are subversive, but not obscene. That's what I'm talking about.