Is it considered a sin for a committed young man to step forward to lead the prayer (Imamate) to fill a void and avoid discord, while those more qualified refrain from doing so?

It is disliked to jostle for the imamate. The one with the most right to lead should step forward. Abu Dawud narrated a hadith from Salamah bint Al-Hurr from the Prophet (peace be upon him): "Indeed, among the signs of the Hour is that the people of the mosque will push each other, not finding an imam to lead them in prayer." Al-Munawi said that this is due to the scarcity of knowledge and the prevalence of ignorance. If your recitation of Al-Fatiha is free from clear mistakes, and you are knowledgeable about the rulings of purity and prayer, then there is no sin upon you for stepping forward; rather, you will be rewarded. There is no sin upon others, even if there is someone among them who is better than you, for the people of knowledge have permitted the less virtuous to lead the more virtuous, and an example of this is the Prophet's (peace be upon him) prayer behind Abdur-Rahman ibn Awf. Ibn Abd al-Barr said: "The imamate of the less virtuous is permissible in the presence of the more virtuous, if the less virtuous is qualified for it."