There's been much speculation as to why Amelia was made to look this way, and made the villain but I have an explanation I haven't heard others mention:
The canon character in the game is not male.
When I watched the Synthetic Man playthrough of it, the default character on the character selection screen was female. Amelia was supposed to represent the "bad friend" of a female player character.
Charlie is envious of Amelia's online popularity she gets from posting dank meymeys online on her social media and makes them feel like they should join in to be popular. Something that is more female coded than male coded. Female Charlie has a brighter color and Charlie is framed as uncertain, just wants to make friends, fit in, and do the right thing. Very blank slate female protagonist energy.
Amelia on the other hand wears a choker, a cooler color pallet, and starts conflict. She's not afraid of engaging in petty crime, or using social media to advocate for taboo things. She's funny, but she's also dangerous, and spreads gossip. You never once hear about her parents or her life outside of her devotion to the cause, other than she's kind of popular online despite having only you as a friend irl.
I'd bet that the story for the game was written by a woman with the perspective of young women in mind first and then did a male character skinswap. She's written as the "bad" girl, not to be confused with "bad girl". She's s social outcast who starts conflict for "no good reason" and even dresses a little evil too with that choker. She's not the good girl who has friends, teachers, and a loving family. She's not a good girl like you are.
The problem with this is that no one loves a blank slate protagonist. At least Amelia cares about something other than getting by. She gets results too with her meme profiles, and as seen in the alternate ending, when the whole school turns their back on the main character, Amelia is there to vent and relate to. She's real, genuine, edgy and rebellious in a way that makes sense. A type of woman guys love.
The constant use of "they" and slip of "he's" poke holes in this theory that the game was made female first, but outside of pure incompetence it's the only thing that makes sense to me.
This is an interesting one.
