Why can't Facebook just have a membership fee? I don't mind paying a small amount. It would drastically reduce their user base but it might just be better for

Why can't Facebook just have a membership fee? I don't mind paying a small amount. It would drastically reduce their user base but it might just be better for society as bot accounts would be difficult to make, younger children with responsible parents won't be able to join (it's a monstrous website that is full of frauds, conspiracy theorists etc and children shouldn't use it IMO ). I know it's wishful thinking.