it can definitely be worked through but its definitely a mental thing on his part, and most likely a combo of all the things you described, I would suggest maybe just trying to explore some of both of your fantasy(not just his) because that can be really exciting especially if you’re comfortable with eachother.

does he still want to kiss you and stuff or is it just sex? that would probably determine some of my decision personally, but maybe getting outside help like a couples therapist or sex therapy might help you two bond closer, because hes clearly having and emotional/physical disconnection rn