I think its a demand issue, not a hardware/software one. Chinese manufactures are creating Mini IPhone 16 and Mini S24, devices that look good, can play music, have the functionalities of a smart phone, and sell for $50-$100.

Parents will probably buy similar devices to their children instead of an MP3 Player. You have an unconventional parenting style not to get your son a phone at 14. Don't get me wrong, I respect that, but there isn't a lot like you to warrant a demand beyond what's currently available.

OP says son is 10 years old. (not sure if it was edited)