Promoting abstinence is a bad thing?
According to the data, yes, it is.
I think we have to be careful about all the different things that are tangled up here.
If promoting abstinence means avoiding teaching birth control or prevention of disease then it may show up as a bad thing. That is the way that I think it is taught to often -- as the only thing to teach.
So it may be that NOT teaching other things is the bad thing not that promoting abstinence is itself a bad thing.