IIRC, it is working, but not showing. It is because "Social Manufacturing" isn't actually broken down anywhere (what you are pointing to is "Manufacturing"). But I have tested this early game (when it is the easiest to see what is happening) and buildings are quicker to build on all of the planets that have bonuses to "Social Manufacturing".
I'm sure someone else can explain it better than I as I am still a little fuzzy on "Total Manufacturing"/"Raw Manufacturing" and so on.
