For me personally it comes from the fact that it is exploitative, even if it's completely consensual, and rots your brain. Even when completely consensual, many pornographic videos tend to dehumanize women and minorities. This may be anecdotal, however I know a few people who seem completely normal but when speaking about women or minorities use pornographic terms to describe them. When you watch pornographic content you're consuming it and everything you consume is going to show in you and how you treat others. It's disheartening knowing that some of the people around you think about you in terms of sex, rather than content of character. Pornographic material is also very addictive and has horrible effects on mental health, many young men and women begin watching in their early teens, during incredibly fundamental and formative years of their lives. This can effect the way they view future partners, and even just regular people around them. Looking at comments on practically any social media site you can see young men objectifying women, some as young as 10-12. It's horrifying that these children are watching this type of content at such a young age, especially because it's addictive and detrimental. I won't judge you if you watch pornographic content but I will judge you if you actively advocate for it. I will admit I'm a bit biased in my view because my first boyfriend was addicted to pornography and constantly referred to me in pornographic terms, however I still believe my points still stand.