8 month old sleep

Our 8 month old is such an amazing, happy baby but is such a terrible sleeper and we are struggling with how to help him improve. Most nights he will wake every hour and will only go back to sleep if he is picked up and rocked which gets him back off quicky. He does not wake in hysterics but will cry which worsens to hysterics if he is not eventually picked up.

My wife is incredible and does most of the night shift as I am working full time. I feel so sorry for her and try to help where I can but I did honestly (perhaps naively) think that by this point, he would be sleeping better.

We tried him in his own room for the first time last night and he had woken up 13 (yes 13!!) times by 5am, when I eventually took over.

I think the issue is he now has sleep association with being rocked which is now a habit and is hard to break. Anyone had anything similar?