"Am I the only female nerd... ahem bitcoin user haha ?"

Right, because that's even a girl to begin with.

Sorry, let me clarify:

Either 15-year old girl's first time on internet and seeking attention because she just found out what her gender can do, or G.I.R.L. troll.  In the former case, "Tits or GTFO" is not derogatory; "Hi look at me I'm a girl" is self-depreciating in and of itself, and responding to it with "if you want me to do so I want to see your tits" isn't degrading the poster any more than they already did to themself.  In the latter case... who cares? It's a troll.

Do you ever see posts that begin with "Hey I'm a guy" on any forum that has nothing to do with gender?  No, you don't.  You see girls (or male trolls) doing it everywhere, though.  Why?  Who knows.  All I know is laughing at their buffoonery is amusing for me, though.