I think that it often comes down to the essays and the letters of rec. If his recommenders say “best student in my 10 years of teaching,” it definitely helps. As for the essay, there are many resources that talk about how to address this. If his essay appeals / entertains the admissions officer who was assigned to his application, then that AO will try to fight for your son.
To score a 36 in ACT at his particular public school is probably truly rare and impressive. Lots of applicants with 36s will be coming from highly academically rigorous HSs. So I’m sure that he will have experiences that are different than other applicants in just some of the most simple or basic aspects in his day. And I think that a kiddo from a Title 1 school would contribute lots of compassion and empathy for ESL students and would be a great asset to Yale or most other expensive private college. His achievements will look good in context of his HS opportunities bc his ACT, SAT2 and APs show an objective level of competence.
“Social life and school spirit matter to him”…maybe consider Penn also.
Best of luck!