It's not Steemit alone which can help developing countries but I think the whole crypto world could help people there.
There are so many which suffer from corrupt governments, maybe not even able to make a bank account or struggeling to make a living. Here crypto can help a lot, and Steemit can provide a daily income for those people. I saw some stories here on Steem from people, coming from developed and also developing countries which total changed their lifes as they finally got the chance to get some income to help themself, and that is something really amazing and nice to see.