Is one who abandons leading the prayer (Imamah) sinful if the congregants refused to pray behind him unless he supplicates for them in an audible voice after the prayer, knowing that the regular Imam is not proficient in the rules of Tajweed and the articulation points of letters?

A person who clarifies the Sunnah and has the right to prevent the continuous practice of congregational supplication (du'a) after prayer, and the worshippers' mistreatment of him by preventing him from leading the prayer, is rewarded for clarifying the truth. They (the worshippers) should continue to advise him with wisdom. As for an Imam who makes an obvious mistake (lahn jali) in reciting Al-Fatihah, prayer behind him is not valid. However, if he establishes the prayer (i.e., performs it correctly in other aspects), then prayer behind him is valid. The most preferable is for the Imam to be the most proficient in recitation. If the choice is between an Imam who makes mistakes in recitation and another proficient Imam who leads congregational supplication, then the more proficient one is more deserving.