Is it permissible for someone whose recitation of the Qur’an is better than others, but who does not perform rukoo’ well, to lead people in prayer?

The most deserving of leading the prayer are those most knowledgeable of Allah’s Book, most learned in the jurisprudence of prayer, and most diligent in performing it correctly. If someone does not perform the prayer well, or a pillar thereof like the bowing (rukūʿ), and their inability is due to an excuse like illness, then their imamate is valid. However, if it is due to ignorance or obstinacy, their mistake should be pointed out to them. If they do not respond, then they are not permitted to lead the prayer, as their prayer would be invalid due to their abandonment of one of its pillars.