The thing is that both of us can speculate as much as we want, but it is really impossible to really determine the real reasons behind the decision. Could you, 100% assure me, that if SE could make more money by introducing children without any kind of negative repercussion, regardless if it was moral or not to do so, they wouldn't do it? I would say is impossible for you to do so, just as much as I can't prove that they would introduce them under such (impossible) circustamces. The problems it would cause ultimately lead to them risking the game, which is one of the main sources of income of SE, together with mobile games, and one of their few recent successful IPs, both economically and critically. Look, I do not doubt that developers like Yoshi or his team had strong moral sense and they do feel very personal about the issue, but I think it is important to consider that Yoshi hands are "tied up" to a certain degree about what he can or cannot say or do by SE. I do not even disagree with the decision, it is the most sensible and reasonable one, even if I feel sorry for those that wanted to play as young characters, but I think is naive to think that a company as big as SE, which has quite a questionable history when it comes to some of their decisions, hundreds of people with different believes working together, a company focused on creating products and entertainment, would mainly concern itself with ethical issues when making decisions.