anyone else annoyed by "tomboy"? why can't a girl like all things and still be girly?

Ma
I posted a pic of my DD wearing a "boys" onesie (blue with space rockets, planets , and stars) and someone said - oh she's already a tomboy. 
1. She's only 2 months old and has no concept of these stereotypes/labels
2. Astronomy is my favorite thing to study and learn about 
3. It's just overall annoying that if girls gravitate toward predominantly male activities they're tomboys and if boys gravitate toward predominantly female activities they're sissies ☹️
End.