My view is that any porno or erotic material that isn't made by exploiting people is fine to use, and that spouses don't get to object to it any more than they get to object to what novels their spouse reads for fun.

I also think that it's rude to read your novel if your spouse wants to interact with you, and rude to read your novel aloud to your spouse if your spouse doesn't want to be read aloud to. The same goes for porn: If you like it and your spouse doesn't, then consume it when you're not around your spouse. (I don't mean be secretive about it, just don't rub their nose in it.)

As for how porn affects how people look at themselves and others, and how it changes people's expectations of real relationships, and whether it creates intimacy issues...this depends on the people involved. Insofar as consuming media affects these things for the worse, I believe that all media and not just porn can affect these things. So it doesn't make sense to single out porn for criticism.

By the way, I am 44 years old, female, and I consume more porn (mainly comic books) than my male life partner, with whom I have a good intimate relationship.