The young will come back if the Church has prophetic leaders.
Pope Francis is half-way there, but the bishops are definitely NOT prophetic - apart from a very few. (Blase Cupich, Geoffrey Robinson and of course Bill Morrison of Toowoomba come to mind).
After all, Jesus was able to attract a huge following in a fairly short time with His message - which of course eventually brought him to the attention of the Temple Police (just as happened to Bill Morrison).
BTW, this also disproves the assertion by conservatives that Jesus was "counter-cultural", so as to justify their own stance against the naughty secular world. He was not. If he had been, the crowds would not have followed him. He was counter-establishment (i.e. the Pharisees, not the Romans).
Not the Romans? Well, it was obvious to Pontius Pilate that the Pharisees had brought trumped up charges against Jesus. (Hey, "trump-ed up" - I like it!).