Is the failure to denounce an evil verbally, upon witnessing it in public places, considered a sin due to shyness?

Blameworthy shyness does not justify abandoning the condemnation of evil. Condemning evil is a communal obligation (fard kifaya); the sin is lifted from the individual if others perform it, and all are sinful for abandoning it. If evils become widespread and a Muslim is unable to condemn all of them, he may be excused, for Allah Almighty says: "Allah does not burden a soul beyond its capacity." When evil spreads and the righteous become weak, a Muslim is permitted to focus on his own well-being.