For kids who are so smart that those programs aren’t enough, it often stops becoming a question of money and more just numbers- kids that are 1/100,000 level smart and live in an area where there are a million people, then the school system sees less than one of you per year/grade. There aren’t enough “peers” to get a full class together.
I’m with you that GATE programs are beneficial and worth funding, but there will always be exceptions that a general program can’t cover and I can believe this kid is one of them.
For my family the problem with gifted & talented programs was money. I did end up taking some courses at the local community college. But e.g. when the opportunity to participate in the Johns Hopkins CTY program came up, my parents couldn't afford it so I did not do so.
(In fact in adulthood I ended up teaching at CTY for three years. It is absolutely a program I would have benefited from as a youth, but very much skewed toward children of wealthy parents. I distinctly remember one session I taught, how much trouble the one public school kid had fitting in. The kid who flew in on a private jet found more in common with his classmates.)
Better is to get said kids into programs with other smart kids their age, where they can be intellectually stimulated, but continue to develop normally socially. The younger the better; suddenly being tossed into such a program after being the smartest (and possibly most isolated) kid in the room for a decade doesn't bode well for one's psyche either.
Wealthy families effectively have access to such programs via private schools, whose curriculum is often a year or two ahead of public schools. Good luck finding such a setup in a public school system, or even finding public school teachers who can provide adequate individual instruction of advanced students: the pay to retain such teachers isn't there.
I don't know what the solution is, but I think it at least involves funding public school better.