I think we’re using two different ideas of agricultural efficiency, you seem to be using the idea of most amount of gain from x amount of area while im using the idea of most amount of gain from least amount of manpower.
Also I feel like comparing African subsistance farmers to say urbanized European factory workers is a bit unfair.
Also im aware of how good groves of apples, oranges, and pomegranates can be. My family grew oranges up until the early 80s, its just that historically theyve kinda been luxury foods and still are a pain in the ass to harvest. The only reason they are cheap is cause of cheap labor and subsidies. Sure on the small scale their fine but once ypu get more than three it becomes a pain in the ass and the crows get drunk.