Perhaps it would be worthwhile for you to engage with the scientific literature cited in this article? These arguments are considered.
Indeed, even in TFA:
> Failing to provide an appropriate education for students who are gifted increases the risk of mental health issues, boredom, frustration, developing behavioural problems both at school and at home, leading to disengagement and dropping out of school.
> When these students are academically isolated in a non-selective school, they can “dumb down” and underachieve to improve social acceptance by their peers and minimise the risk of bullying and social isolation.
We can disagree about these conclusions, but I hope we agree that if they're right, it's not morally right to send a gifted kid to a regular school on the theory that they'll set an example for those around them if the above is the cost to the kid.
These arguments seem to be true, but I'm sure there are similar facts telling us that without smart kids around other kids can be harmed in similar ways. So it is kind of smart kids well being against other kids well being. So why smart kids well being should be more important than others? Especially taking into account that smart kids tend to have better families and opportunities to get what they need without going to special schools, while "dumb" kids are often "dumb" because they have no choice and their need for support is more urgent.
> I'm sure there are similar facts telling us that without smart kids around other kids can be harmed in similar ways
My point is that rather than assuming things we think are probably are true, we should try to argue from data. Especially since people have studied this, both professionally and experimentally.
I can think of plenty of ways that your argument might not be true. For example, per TFA, if gifted kids act up or intentionally tank themselves in "regular school", then maybe it's worse for everyone for the gifted kids to be in "regular school".
Maybe that's true, maybe it's not. But rather than making guesses based on nothing but our gut, why don't we consider the experts' studies and opinions?
Indeed, even in TFA:
> Failing to provide an appropriate education for students who are gifted increases the risk of mental health issues, boredom, frustration, developing behavioural problems both at school and at home, leading to disengagement and dropping out of school.
> When these students are academically isolated in a non-selective school, they can “dumb down” and underachieve to improve social acceptance by their peers and minimise the risk of bullying and social isolation.
We can disagree about these conclusions, but I hope we agree that if they're right, it's not morally right to send a gifted kid to a regular school on the theory that they'll set an example for those around them if the above is the cost to the kid.