If James wants to be a scientist doing research on X but his society already has enough scientists doing that work, James can't make a useful contribution to the cooperative effort. If instead, his society is in dire need of research on Q,R and S, James might be given his choice of training to specialize in Q, R or S and thus make a worthy contribution.
I find it interesting that you have James becoming a scientist instead of a poet or a social worker.
As to James wanting to research X and you wanting to discourage him or redirect him to other problems I see as problematic. You give the impression that a person of a certain IQ is a tool or cog that can be applied or directed to a wide variety of problems interchangeably. Who's to say whether its James' passion and interest in problem X that results in his making actual headway into solving problems related to X, despite all the other people that have been working the problem, yet have made no progress.
I don't think you can create or direct someone to be the next Newton, Einstein, Ghandi, MLK etc etc. All are a unique product of nature, nurture, and a particular moment in time.
I think you have over-estimated the degree of difficulty. Our system of education is the immediate problem. With a computer assist, we need to track students from grade one on. We'd need to know what they're good at and where they fail. We should be able to identify our scientists and engineers by the time they reach middle school. How much money their parents have should nothing at all to do with their further education or future employment.
Again, you have heavily emphasized science and engineering. Interesting. You also seem only to want to identify and focus on the very brightest. If average intellect kids from supporting, resource rich homes presumably have a better chance in life, wouldn't we also want average intellect kids from poverty or low resource environments to also have the same life opportunity as their more well-off counterparts?
So, a personal anecdote. I live in a small city that is home to a State University. I and my family live in a city neighborhood that is in walking distance to the public elementary school. Our neighborhood is middle to upper-middle class, with many professionals and university professors with families wanting their kids to attend this elementary school. Fifty percent of the kids at the elementary school come from the surrounding middle and upper-middle class neighborhood and the other fifty percent come from low income and subsidized house neighborhoods.
The school works hard on not segregating kids by ability, keeping classes fully integrated with the exception of additional gifted and talented curriculum 3 hours a week starting in 2nd grade for those who test or a recommended for it.
The disparity starting in kindergarten between those from middle/upper class homes vs low/subsidized homes is stark. And starting in kindergarten and despite community volunteers and teaching assistants and university education majors doing rotations in the classroom, the gap in performance grows to a constant 2-3 year grade level disparity as the students progress through elementary school.
I think you underestimate the impact environment has in child development and readiness to learn in the 0 to 4 years. Once in school, home life continues to have an impact on the academic success of the students.
Perhaps volunteering in a low income school might give you some experience of the seeming intractable problem of overcoming a students challenging home environment solely in a classroom setting. You will see that many disadvantaged students are already well behind by 1st grade relative to those who come from more well-off homes, a deficit that is quite difficult to overcome.