(nsfw) What's with the taboo with pornography?

does anyone appreciate the slight pun that I made? xD I thought it was clever.

Anyway, I remember growing up and hearing from people like teachers, pastors, etc. that pornography is bad, but, what really is wrong with it? What was the reasoning behind people saying that?

I know that it would be bad for my age when I heard it (since I was under 21), but what is wrong with it?

I mean, pros and cons and all that good stuff.

Sorry if the question doesn’t make much sense… I was struggling with how I could ask it correctly.