Statistically, trad young adults are just as infected with 'the world' as any other young adult population. As atheism is growing, so a small % of trads will be infected with this and their Faith will become lax and they may stop going to church for a while. I've seen this more than a few times.
As the indult grows, a large % will leave tradition and attend this. At our chapel, we've lost about 70% of one generation to the indult. Young adults, who haven't read anything about V2 or the new mass, who only care about social media, get duped by the 'positive and happy' novus ordo-ites who think that "the latin mass is coming back! Everything's going to be rosy". Plus, the millenial generation cannot stand to be an "outsider" or "different", as they want to be "part of the group" just like on facebook. They compromise their faith because of human respect. ...Or they started dating novus ordo/indult catholics and didn't want to 'rock the boat' by trying to convert them to tradition. So they compromised and went to the indult, for love.
Then, there's the normal % of trads who have just given into a partying/fun life. They may still go to mass, but their faith is very weak. A good percentage of these will 'grow up' and become decent catholics at some point. But, some will not.
Finally, there are some who have kept the Faith, lived 'boring' lives, are looked at as 'old fashioned' and who have grown in virtue. These are small in number but they are a great example.
Really, aren't the above 4 categories consistant with the parable of the "Sower of the Seed"?