I feel like I'm talking to a brick wall. Or maybe you don't understand what heterogeneous masculinity means. I assuming you were talking about hegemonic masculinity - the dominant form of masculinity in this country which involves lots of ugly stereotypes that puts guys in boxes such as men shouldn't be emotional, shouldn't stay home with their kids, shouldn't work in female dominated professions such as teaching or nursing, etc etc. These things have nothing to do with testosterone. These are gender roles and the problem is that they assign non-gendered traits (nurturing, ambitious, driven, career focused, child focused, etc) with genders therefore putting people in boxes and making it more difficult for people to be authentic to themselves because if they don't fit into whatever particular box they will have negative social consequences. That isn't biological, it's societal, so I don't understand the fascination with testosterone - it literally has nothing to do with anything we are talking about here.