If i own a Rolls Royce and if it is banned in countries like India and China that does not mean that i will not get a good valuation outside those region, when it comes to bitcoin the main difference is that bitcoin is a not a material object but that can be traded world wide without any restrictions and hence your assumption that it will be worthless is just a joke, these countries might be ruling by stupid people who does not understand how technology works but that does not mean that it will be like that for the rest of the world and people dealing with bitcoin will trade outside their restrictions and there is nothing they can do about it.