Not just treated with "disdain" by the elites -- middle-class gifted children are hated and feared by the elites, because they are competition to their OWN little darlings.
There's a phenomenon called "regression towards the mean". It means that the children of the very successful will not necessarily be as smart as their parents (but probably will still be above-average). How do they ensure their own next generation will be able to retain their positions in the halls of power? By making it harder for the exceptional children of the lower classes to not get the opportunity to successfully compete.
No amount of fertilizer will make a maple tree grow as tall as an oak. The only way to keep them "equal" is to take an ax to the oak.
Exactly; the snobs need to keep everyone in their ‘’by Grace of God’ place via birth.