iPhone internals are difficult to repair, but they make up for it with reliability. If OLPC had hit that target they could have been successful but it was basically not achievable for a mid-2000s laptop.
The nice thing is they have come a very long way in terms of battery replacements. You can get it done by apple for quite cheap and soon you will be able to buy the battery officially.
But improving phone repairability wouldn't really do much for poor communities because it is more economical for them to just buy one of the dirt cheap working phones on the second hand market. You would never bother to fix an iphone 5 for example when you can get another working one for almost free.
And if you do find alternative parts and offer repair services to the public they prosecute you and destroy your life
The problem is a lot of the parts that tend to fail like a $part cost as much in parts as the $device is worth.
A general problem leading to too much stuff into garbage.
Anyone coming up with a beneficial solution to this general problem might just win themselves a Nobel Prize.