“Reproving at times with sharpness” often is couched in terms of “preciseness” and “focus” rather than “blunt challenge” (much like operating with a sharp surgical instrument rather than a butter knife) - and it is followed immediately by “when moved upon by the Holy Ghost”. That puts a very limited application to “sharpness” and says, in essence, that meekness and patience and long-suffering are to be the general rule.
Our doctrinal and historical traditions allow for sharpness and upbraiding, but they also restrict that type of language primarily to correction of the Spirit - immediately followed by an increase of love. If there is a generic form of Mormon communication that covers a call to repentance, I would submit it is communication that is focused strictly on the issue, prompted by the Holy Ghost (a stricter standard than even righteous indignation) and then immediately dropped in favor of a loving verbal embrace.
This is my take on communal calls to action in the Church. Since individual members are at different points in their awareness and activity and living in countries where the most important non-Gospel issues are so diverse, it is hard for church leaders to offer “sharp” (meaning focused and precise) calls to repentance to the membership in general outside of Gospel basics. I know even on the ward and stake level, that would be difficult to see happening - much less at the global level. About all they can do in areas that are not integral to their main mission is set a good example, teach correct principles and let the members govern themselves.