Your mistake here is in assuming you're replying to someone who identifies all sex as objectifying. Chirs is responding to an AC who spoke of why they like sex in entirely selfish terms. "I like it, it is in my nature." AC chose not to, or neglected to, mention whether they enjoy giving pleasure to their partners, which would be a more altruistic (except in a very cynical sense) reason for liking sex. Chirs is just identifying this as potentially being a sign of objectification.
If AC had said "A very important part to me is that the woman enjoys it too." then Chirs would have been unreasonable in saying what they did.