As a child psychologist, tjb33 is understandably sensitive to this issue.
Tjb33, if you see other indications that this person is not good for a boyfriend, then consider those issues. (Lack of openness to counseling is a red flag for me too.) However, do not make all your decisions based on this one thing (teen porn). It's an instinctive thing for men to like younger women, but the vast majority of men do not act on that instinct in real life. Keep that in mind. You happen to see the results of the worst offenders. So your view is skewed, and understandably so.
What men like in porn often has no bearing on what they would do in real life, it's a fantasy, like a good book.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
(Please note, we give the best advice we can based on the information given in a post. For better advice, please include the age of all romantic partners.)