The premise of treating everyone equally under the law (or otherwise) despite knowing for certain that not everyone is equal is that it helps prove beyond reason of doubt who the elite truly is. That is, the top contributers are in part there because of socioeconomic factors, exeptional parental support or a culture of sorts (Think Chess versus Go) But trying to at least give everyone resources to compete helps us find the exeptional few.
I'm not sure what you mean by "premise", but I really hope that the justification for "treating everyone equally under the law (or otherwise)" is not because doing so "helps prove beyond a reason of doubt who the elite truly are". For that would imply that if a better way is found of "proving" who the elite truly are, we could abandon the idea of equal treatment. Or that we could abandon equal treatment if we agreed that "proving who the elite are" is actually unimportant. In fact, I'm personally skeptical of the value of "proving beyond reason of doubt who the elite truly are", but also highly committed to the principal of equal treatment, so I think the two are unrelated.
As I understood it: since we don't know who the exceptional few are, we want to give a fair bit of support at the start to everyone, this will allow the hidden talents to show up.
"For that would imply that if a better way is found of "proving" who the elite truly are, we could abandon the idea of equal treatment."
In a way this already happens, equal treatment is out the window as soon as a doctor makes an assesment based on race or gender or country of origin. the basis of new drug trials is to make a representative 'equal' group of people. however in its wake if certain drugs are found to interfere with pregnancy then a doctor will not treat patients equally. In law beside the requirement to have a law degree, certain companies want lawyers from prestiegious schools or with exeptional grades. there is no equal chance to get hired here. Though what is a danger for these companies is that the grades and graduation process must not favour any particular candidate on anything other what the company wants to select for (Merit). if their grades are not aquired trough a fair process then companies will lose more and more of their guaranteed value.
Equality seems to serve as a way to find the exeptional few and prove by the many thousands in the same bracket that their skill is based on merit.
