1)ND will never be able to compete with the Alabamas of the world for certain because ND expects its athletes to graduate. Alabama et al really doesn't. That is a given. It isn't going to change and it shouldn't.
2)A huge majority of the high level recruits out of high school all aspire to the NFL. But, given #1, it is just stupid to limit your recruiting to those who are so myopic that that fail to realize the the 'success' rate from high school to pros is really really small. Those types of athletes are unlikely to be interested in putting in the academic effort required at ND and aren't going to last very long at ND anyway.
3) I doubt that many players during any era at ND went to ND because their path to the NFL was a prime motivator. I am sure there were some but overall I highly doubt it. Being around many of them during my time at ND, I doubt I heard the world "NFL" more than a handful of times from All American players who did end up in the NFL and actively recruited by schools like Oklahoma, Texas, OSU and Alabama.
Overall, yes you want kids at ND who aspire to the NFL. But if that is their prime motivator, they are unlikely to survive at ND academically and will chose other schools because other schools will let them do nothing but the theory of offensive football classes, programs that exist only for athletes, open book tests while tutors complete their assignments, etc.
The problem isn't getting good enough players to come to ND to win NCs. It is making sure that we have the coaching staff that knows how to coach there.