what is stopping them ? corrupt governments, extreme poverty and that's the beginning of the list
Discussion
If they have a laptop or PC and at least occasionally an Internet connection, they can build and market a Nostr client.
these are people struggling to survive day in day out. It is a problem when one tries to build for the world and don't understand the world enough or local cultures. I am not sure why you are so triggered or insecure - but if you think you can build solutions that can benefit the world by all means go ahead.