Okay, smart guy. If you wanna talk about trans girls' junk, then I'll oblige you.
First off, you can take pills instead of injecting, and your balls shrivel up on their own without the need to have them removed. I produce less testosterone than most cis women, and have for literally years now. I don't even need to tuck, because estrogen shrinks your dick so much. You couldn't find my balls with a map and GPS. My ass is fucking *juicy* now because I'm pumped up with enough progesterone to give birth. My hips have rotated, and my tits are so huge without any surgeries that I can't run without hitting my own chin.
It's difficult as hell being a trans woman, but not for the reasons you think. Mostly it's about not being able to open jars and constantly being hit on by cute girls who work at coffee shops. I can't tell you how many phone numbers I've walked away with just by smiling at them and saying hi. I couldn't do sports if I wanted because I'm so busy juggling my four girlfriends I'm too exhausted from the amazing sex to even think about basketball anymore.
But, if trans women want to compete in sports, they should be allowed to if they've been on estrogen two years. If cis men want to compete against women, then all they should have to do is get on estrogen for two years. I bet a good portion of them will be so happy with the estrogen they'll forget to stop taking it.