If somebody wants to slip into female-only spaces for nefarious purposes wouldn't dressing up as a Muslim woman be a better approach? Someone who is open about the situation (female with a visible dick)
There are zero females with dicks, visible or otherwise.
Wrong.
Even if you are determining sex via chromosome pattern, there are female persons (XX) with penises, just as there are male persons (XY) with vaginas. Exposure to testosterone in utero changes the physical form of developing female fetuses, as does resistance to the effects of testosterone in males. And then there are the persons with rare chromosome patterns (XX/XY, XXXY, etc) who may be female but still have male attributes, including penises.
You keep dismissing gender as nothing more than the thoughts in a person's head and relying solely on physical attributes to enforce a strictly binary view of sex. Not only are you ignoring the existence of intersex persons, you're ignoring sexuality itself.
Human sex, sexuality, and gender, in both form and expression, are not binary.
Boobs are TERFs.