I think most people’s view of gender and social expectations of its performance are just very unexamined, because they never have cause to examine it and when they are presented a cause such as trans or gender non-conforming people their reaction is confrontational and defensive about their basic assumptions which they never challenge.

I actually think a lot of people who are not themselves trans or gender non-conforming but accepting of those tend to also be accepting broadly but not understanding of these performances or nuances that are constantly reaffirmed through social interactions and can require deconstruction to properly perceive and present.

I am myself cis-male but despite occasionally being confused for a girl in my teen and young adult years it took me until my mid 20s and interacting with trans people to see.

Is your mom someone you see often? I only noticed how much my boyfriend’s voice had changed from testosterone after watching an old video of him, so I think maybe changes like that can be harder to notice if you spend a lot of time together.