Sin is sin. Sin is defined as a transgression against the Character of God, the Word of God and the will and ways of God. Therefore man and government cannot define what is sin and what is not sin.
Although all sin is equal in status as being a transgression against God and His Word, not all sin carries the same weight in judgment and consequences. In the Old Testament God commanded a blood sacrifice for some sins yet for the sins of murder, and all sexual sins the offenders were stoned to death. Sin was sin but each carried different consequences of judgment.
When we teach and live the life of holiness and righteousness, which is the life of Christ in and through us we naturally stand against all acts of transgression against God.
We cannot speak against every sin or that is all we will do. In fact most sins, especially within the body of Christ are sins of thoughts and intentions of the mind and heart and not in deed.
God could have mentioned thousands of sins against Sodom, but He singled out the one that caused His destructive wrath and that was homosexual sins.
God could have mentioned thousands of sins about the people of the earth to Noah, but He mentioned the one that caused His world-wide destruction of the earth, and was that violence had filled the land.
So although I agree that all sin is wrong and should be addressed, however some carry such a destructive nature and are such a reproach to God that we need to call the nations to repentance against them.