Great points!
One thing I wonder though, is porn a fundamentally unique art form? Unlike sculptures, music, or paintings which are mostly enjoyed individually which reenforces dopamine-releasing brain connections, porn directly influences the important real-world activity of sex which is not an individual activity. It involves someone else. The porn we program ourselves to enjoy does influence our expectations and pleasure response in the real world. If it's an honest representation and the people involved in the real world who genuinely enjoy the process via mutual consent, more power to them all! But that's so far from the norm that I think some shaming may be in order here.
Let's try another example: If we have art which represents a certain ethnicity as being subhuman and that art directly influences how people who enjoy that art treat those people, we can directly say, "Hey, that art is immoral. We should shame those who create it and those who enjoy it." The key here, to me, is that it's fundamentally based on a lie. There are no subhuman ethnicities. As you said, "pop" porn creates a fiction that women in pain or at least discomfort are actually experiencing pleasure. It's a lie. Not only is it a lie, it directly influences people in real life.
I'd love to know what you think of the post I linked to at to top. She goes into much more detail and quotes professionals in the porn industry to make her point. Porn based on lies about female pleasure does negatively impact real-world human intimacy which, to me, should be shamed because it does directly impact human wellbeing in negative ways.
Can we also support positive education about porn which isn't based on lies? For sure! Because things are so far in one direction now, I think a bit of shaming is called for. Many young men, I imagine, don't even know they are "learning" something which will harm them.