I've seen the very lifelike robots in tv news broadcasts, and I think it's scary to see how real they appear to be physically. They are, of course, artificial, man made, not real. But to use the word "friend" with its connotations of personal connection, shared life experience, love/affection seems to put a futuristic twist into the mix. Is it possible to manufacture friendship? I don't think it's possible no matter how far technology advances: human friendships with all of their "messiness" are real, vital, and essential. I think the author uses the term AF to guide the reader to question whether in the future we want to trade the real for the artificial even in such important daily interactions with other humans.