Maybe I've just been unlucky, but in my experience retrospectives are mostly virtually identical every time: nothing happens about the frustrations, so they become a complaint session instead of something positive.
Only thing you can do when your manager doesn't do this job is say you will personally take on the extra responsibility for no extra pay and no reduction in other tasks and give most of the credit to your manager. Then if you are lucky all of this extra work might lead to a promotion far down the line, or it will go to the person who were more positive during meetings making the manager like him more and all your work fixing things got wasted.