Would a Muslim be sinful if he did not denounce the abuse of Islam and the Prophet Muhammad (peace be upon him) by words or drawings, and would the sin be lifted from the rest if some did so?

Originally, enjoining good and forbidding evil is a collective obligation (fard kifayah). If some individuals fulfill it, the sin is lifted from the rest. However, it may become an individual obligation (fard ayn) if no one else knows about the evil or can remove it except for that person. Muslims are obligated to carry it out in compliance with the hadith (definition): "Whoever among you sees an evil, let him change it with his hand; if he is unable, then with his tongue; if he is unable, then with his heart." The obligation to forbid evil is emphasized whenever the evil is greater, especially blasphemy against Allah, religion, or the Messenger. Whoever becomes aware of such an act, or is informed of it, must forbid it according to their ability. For the abundance of those who forbid evil intimidates wrongdoers, demonstrates the strength of the people of religion, and earns reward.