Yes, we do want talent to rise. But what if we're so overly worried about incompetence that we're overlooking the opportunity to increase talent across the board? What if the way we keep incompetence out is actually preventing ten times as many people with potential from reaching their potential?
Yes, poor kids shouldn't be locked out. The issue is that meritocracy may be providing the illusion that poor kids are not locked out, because they're allowed to "try hard", while in actuality being a major mechanism for locking poor people out. By filtering for the byproducts of privilege, people can claim to not be filtering for advantage while still filtering for advantage, right?
I don't have good answers either. Ideas like basic income and free education seem like potentially good starts, but there's certainly a lot of political agendas and dogmatic opinions surrounding those ideas. This week I'm just feeling like the solution somehow has to invest more in those without as much access without obsessing over the individual returns. It should be okay for society to try to educate and support poorer people and not expect each and every one to make it. For some wealthy people, I suspect their deep down collective cultural fear is that if you gave all poor people enough money to have stable home lives and not have to worry about money, and sent them all to the Harvards of the world, that just as many poor would succeed as rich succeed. That would undermine the idea that we need to filter for talent, and support the idea that we need to nurture talent instead.
(A side note: Talent may be largely derived from riches, but rich parents definitely don't always result in talent. There can be, and are, incompetent children of the rich.)
First issue: We want the people with talent to wind up in the positions that need talent. We (society) actually need talent in those positions, rather than incompetence. It doesn't matter whether the incompetent ones are the children of the rich or of the poor; there are positions where we don't want them.
Second issue: The children of the poor (or even middle class) shouldn't be locked out of success in the economy simply because they're the children of the poor. Those with latent talent or undeveloped talent, or whatever you wish to call it, need to have that developed, so that it becomes actual talent. The school system was supposed to be the way that happened, but the school system has largely failed at that task, at least in much of the country. Now what do we do? Can we fix the school system? Or is it just a reflection of problems in society, and we have to fix the society in order to fix the school system? If we can't fix the school system, what do we do instead?
It seems to me that the biggest variable is the parents' attitude toward education. Children whose parents see the value of education will, on average, get more out of a mediocre school system than children of uncaring parents will get out of a good school system, unless they're rescued by someone - a great teacher, perhaps, or someone that they look up to. But if their social capital doesn't include people who value education, and their schools don't have great, inspiring teachers, from where are they going to get the spark?
I don't have good answers for you. I wish I did.