You don’t need to get him anything.

That said the iPhone has a much longer support cycle than any android, my iPhone 11 Pro Max I just replaced still gets updates. I’ll be giving that to my 14 y/o son for his birthday.

I say this as an iPhone user, I held onto my 11 until just recently and really only replaced it because I dropped a plate on it at the gym and cracked the screen.

The 13/14 will probably be noticeably better than the Samsung he’s had and if he wants an iPhone it’s probably for iMessage.

My 2 cents