plenty of explanations for this map: cultural differences in how phenomena are interpreted (what americans interpret as 'aliens' may be more likely to be interpreted as 'angels' or 'spirits' or 'weird imperialist jets' or something in many other cultures without the same mass media sci fi trends in their pop culture, and maybe they are even correct to do so!), less access to electronics like cameras to record sightings, less interest among media industries of other cultures to cover such topics, less military equipment like radars and jets deployed to possibly detect phenomena, less organizations researching sightings in other countries, etc. Its silly to present this one map as some kind of 'gotcha' imo.