Honestly, MLs tend to do this with a lot of convos, I feel.
I can agree with you there. That is reasonable and how opinions work. However the reasons listed are themselves still subjective since they do not apply to a wide array of situations. The problem arises more in attempting to impose that ideal on others who don't hold it.
That is reasonable to do when there are significant moral and ethical issues (CP, Bestiality, Revenge Porn, Rape, exploitatively media, inaccurate depictions, purposeful objectification and so on), but simply stating that sexual material as a monolith is entirely unacceptable would face immense backlash.