>>64608
I think I partially understand it.
Robots are impersonal and non-judgemental, so they serve as good "safe" caretakers in fantasies. You can imagine being forcibly babied by a machine without feeling quite the same sense of humiliation you would at the hands of a human.
I find it hard to fap to all the robonanny stuff though. The lack of realism in the robots tends to trigger my autism. I have the same problem with things like mecha anime too.