Reasons 1 and 2 - Ok, we can leave those out, though I think in our culture Christian marriage is more the norm than not.
Reason 3 - I think that's very hard to argue against. Porn is very exploitive of women. Women are trafficked within the industry, many made to perform sex acts they do not want to do.
Reason 4 - Does porn promote violence against women? His figure given is 40% of porn videos do...I'll be generous and ballpark that to a third. That's still a lot of objectification and violence against women, through male dominance.
Reason 5 - See 4
Reason 6 - Goes back to 1 and 2, but isn't that the thrust of the article? Prager's views on porn in both societal and religious marriage?
Reason 7 - He uses Paul as an example, but his point is universally valid. In a monogamous marriage (and no, that's what we have, not what you would like), when you introduce sex acts with other people into the marriage, you eventually weaken the marriage. Porn is more insidious, since the act is not physical, but it does creates altered perceptions of intimate reality and eventually causes harm.
Reason 8 - Does porn shatter trust in a marriage? I don't know if it shatters trust, but it constantly sends a message to the wife that she's not young enough, not built well enough, not adventuresome enough, not willing enough. In short, she's simply not enough.
Reason 9 - see 8.
Reason 10 - Does porn crush intimacy? Certainly, if the fantasy is replacing reality.
Reason 11 - Duty sex. Exactly what it says.
Reason 12 - Sexual dysfunction. This was the author's cite: https://www.insider.com/men-who-watch-lots-of-porn-worse-erectile-dysfunction-2020-7
You can look up the original paper, if you wish, but the findings were interesting, in that porn consumption and erectile dysfunction seem to be linked in a significant portion of men, especially young men.
Reason 13 - That one is about rewiring one's brain. Again, the author's cite:
https://neurosciencenews.com/neuroscience-pornography-brain-15354/
The statement that porn rewires the brain is the subject of more than one paper. One from PubMed:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3050060/
Reason 14 - again religious.