Tochacha is a Halachah ( however requiring such sensitivity that it is appropriate only in quite limited circumstances in our ignorant generation)
And it has always been our way of Gedolim, Rabbeim, other leaders, and concerned erliche Yiddim to protest againt public and widespread errors of Halachah and behavior, out of concern for those who are jeopardizing their Olam Ha Boh, and out of concern for the Honor of Hashem.
This has always been a foundation of Torah.
The other way is the way of the nations, from whom we have been commanded to separate ourselves.