TLDR: AITA for wanting my boyfriend to clean his side of the room?

Okay this may not seem like a big deal to some people but I feel quite frustrated. My boyfriend(M31) and I share a room (F22). The bed is in the middle: one side is his and one side is mine. I am not the cleanest person and I can admit that. I’ll have some trash or junk, but will usually clean it within the week. I don’t walk on his side of the room but when you walk in the door, you can clearly see his mess. 

He has piles of clothes, bags, other shit that takes up most of his side of the room. It looks so messy and it *never* gets clean. I have asked him a couple of times to clean it up and he gets mad at me. He complains that he doesn’t have enough space to store his stuff, so I suggest we go through clothes together and see what we can donate but he refuses. He gets so frustrated and then refuses to talk about it. 

I have brought it up a couple of times but at this point, he just sulks and nothing comes from it. AITA for trying to get him to clean his side of the room that I think is super messy? Or am I being overbearing??