My thoughts summarized from reading the bible, leadership material, listening to conferences and prayer. Yes, we are to pass on the baton to the next generation, but we are to be the body of Christ working together. No where in the bible do we read that one generation totally steps aside and the younger rules over everyone who is older than they. It is very easy to build a weak church; place young leaders in positions, who are not ready and push the leaders who are older than they are aside. To disciple and train others, we must have people who are further along than us, in spiritual maturity. It is common to hear the verse in Timothy used in this way, "Do not let anyone look down on you because of your age." When Paul placed Timothy in this position, Paul saw a spiritual maturity in Timothy that would assist him to operate as the leader of a church. Timothy was not placed in this position because he qualified as young in age. There are also verses that instruct Timothy how to communicate and be in relationship with people of all ages and both genders.
My final thought; I am secure enough in what I write here to state that; Build a church with only the young, or only the old, and both will be equally out of balance in the area of discipleship and spiritual growth. In fact I am secure enough in this statement to say, both will be very weak churches.
(The The Relationship Project With Nancy J. 2014)