I can't see governments of poor countries jump into Bitcoin by setting up entire mining farms. It will be wealthy individuals in these countries, or investors from abroad that might get to set up mining farms if they find it to be cheaper than going for China to set up everything. If you consider that poor countries have a very poor power network, where power outages are a frequent occurrence, then it's not a very interesting option for them. Don't forget that a lot of these poor countries are not very Bitcoin friendly either. Another negative point that any serious investor is taking in mind.