I'll just post the paper here for now and will come back with a more detailed summary later - it's not published yet but the authors are credible economists.

https://www.nber.org/system/files/working_papers/w29779/w29779.pdf

After reading just the Abstract, I am pausing to share my observation that the study appears to focus on what ongoing ACHIEVEMENTS (such as degree attainment and level of salary earned), if any, are recognized through the years, by gifted children who attended Gifted Children Programming (GCP), as opposed to gifted children who did not have access to such programs.

It has long been my impression that gifted education existed not necessarily to propel children forward for greater achievement, but to meet their educational needs and facilitate their ongoing positive development:
1) the continued growth of their brain via the stimulation of learning something new every day and experiencing appropriate challenge (thereby approximating what many/most children experience in a classroom),
2) the ability for gifted pupils to access a sense of "belonging" via placement amongst the company of their intellectual peers (thereby approximating what many/most children experience in a classroom),
3) fewer gifted drop-outs, and well-adjusted, resilient gifted adults (thereby approximating what many/most children may take-away from their educational experience).

I will continue reading... digesting 124 pages may take a while!

I too have not made my way through the whole document yet...but a couple of my observations so far:

The congregated gifted programming under discussion does not appear to employ many of the strategies we often consider, such as curriculum compacting, acceleration, etc. The GCP students and the non GCP students had access to exactly the same curricula (the top-level bagrut, from what I can tell), and appear to have made fairly similar use of it. Based on the descriptions provided by the authors, in USA terms, the GCP students look more like a tracked AP cohort. I suspect that the actual difference between GCP and non-GCP was access to a community of peers, which appears to have been a very mild negative for the male students, and maybe a positive for the female students, if I'm reading this correctly.

The one substantive difference that the authors identify is greater breadth in the educational path of the GCP students, which I would consider of value not only to society, but also to the individual students. I know I am not alone among the adults on this forum who have delved into our own multipotentiality in ways that don't have obvious career outcomes, but have been personally satisfying.