Let me elaborate on point 2 for you, as a starting point. People that have felt the societal pressures of gender stereotypes that they don't feel fit them almost always have extremely difficult lives and many kill themselves. Raising your kid as gendered increases the societal pressure on other people's kids that are also raised gendered.

But even your kid, transgendered or not, will feel the pressure of gender stereotype. Depending on what country you are from, for example, they will feel huge shame if they are a boy and they cry in public