Random addition to your post…
There’s early/limited studies suggesting the drug valproate, which is used for bipolar and epilepsy sometimes, can re-open the perfect pitch acquisition capabilities of the human brain even if the individual is no longer an infant and has aged past the language acquisition stage of childhood development.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3848041/
Different use of it in an 8 year old girl with language regression: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11230735/