Freshman with no experience, two and three-year starters with no production, with two and three-year proven players from other schools. The latter being better than high schoolers.
Yes, teams can fall apart in the portal Era (Clemson), teams can be turned around quickly as well (Indiana, Colorado) *with the right players*.
ND has a deep roster. I honestly think many on this board are so stuck in the sky-is-falling mode, after decades of losing, that they don't know how to handle the success we are now consistently having.
To be and stay at the top, you have to act differently from the herd. The herd is building for one year at a time with collectives. Those that are different are strategically fixing small holes for the long run.