I am not sure about Mahomes. He has been injury-prone and his style of play does not hold up over the long haul. One of the reasons that Brady and Brees got that amount of volume is because of the way they play the position to avoid massive hits and hits outside the pocket. They also play a very fundamental style of QB whereas Mahomes is unorthodox and puts a lot of stress on his arm/shoulder with all of this highlight reel throws. That style really does not age well and he will not always be surrounded by HoF talent either.