Is it necessary to wait for ten for the chazan’s repetition

According to the opinion of Maor Israel, Maran Rabbi Ovadia Yosef zt”l, although, according to the law, it is permitted to start the repetition of the Amidah with six who have finished the prayer in silence while there are still four who have not finished, “it is good” to be strict and wait for the ten whenever possible. And according to what will be explained below in the sources, based on the responses of Maran Mohar”i z”l, it seems that there is a bit more than just “good” in this, but this is the correct conduct, allowing it only when there is a disturbance for the community, and even then only occasionally (“once”) and not as a regular practice to start with six. However, these reservations are not so explicit, and from what was said orally, there is room to understand that the permission is a bit more comprehensive.