Despite the fact that he's kind of good looking, women probably HAVE actually told him it's his looks that make them not want to date him. This seems ridiculously uncommon from all but the most vain and vapid women (the minority, but incel creeps think they are the majority.) Given how uncommon this seems and how he's not actually ugly, it's probably because his inability to show the appropriate facial expressions for the situation puts him in the uncanny valley, much like his doll. Or maybe he's figured out how to mimic other people's facial expressions, possibly even in the correct contexts, but they don't show in his eyes and it sets off people's alarm bells. Therefore, women tell him this because they are 1) afraid to tell him he's a fucking creep since they think telling him that will make him more likely to kidnap/rape/murder them, or 2) they don't have practice listening to the gut feeling that something is WRONG about someone to correctly differentiate this inability to show normal facial expressions from the looks of his face.
You could attribute this to tism, but I don't think he's autistic. It's true that people are commonly creeped out by autistics for the same reason they're creeped out by psychos (inability to express empathy, read emotions, flat affect), but most people seem to unconsciously understand the difference even if they're not practiced at spotting autists. Women who reject autists usually do so by telling them they're "sweet" (retarded and can't flirt, heart on sleeve) "handsome" (autist face but not ugly), "attentive" (spergy about them and too obsessed), etc, but that they "don't think it's going to work out" (for the reasons in parentheses that they really mean). They don't usually say it's due to looks.
From this fact combined with the other creepy behavior and assuming he's not making it up (big if true!), he sounds like a low IQ psychopath who's too retarded to create masks that actually work to get him around in life and get women.