Not really sure which poor countries you are talking about but in India the smaller the amount, the cheaper it is to transfer. <10k INR is most simplest transac

Not really sure which poor countries you are talking about but in India the smaller the amount, the cheaper it is to transfer. <10k INR is most simplest transaction you can do by simply downloading any payment app and using UPI. >100k INR is where transaction costs usually creep in.