BTC can have a great impact on developing countries, but so far with current user interfaces it's not so friendly towards the masses, we need better implementations of LN and wallets to make it all work.
In developing countries, bitcoin is easily accepted because the country needs so much investment to advance industry, tourism, infrastructure, etc. However, not all developing countries accept with open arms, there are those who reject it as a means of payment, but not prohibited as a commodity asset. Can also be a payment transaction tool.