Scratching one’s balls is a common and accepted pastime for cis men in casual contexts, public or private. You won’t see many men adjusting themselves at their wedding, or at their inauguration, or coronation. But when hanging with friends, watching TV, chilling, it’s not a big deal. Men with cis privilege can do it without being chided or thought disgusting. Balls need adjusting sometimes, and that’s understood.
But vaginas itch too, and it’s not okay for women to relieve their genital prickles when they’re just chilling. Vagina is made of skin, and it’s skin that sometimes gets irritated. For me, it’s particularly bad when I shave off my bush, as I occasionally do - the two weeks after I quit shaving are usually filled with mid-conversation trips to the bathroom just to scratch. Chilling with friends is supposed to be relaxing, but as with many spaces in this kyriarchy, women have additional pressures and requirements to live up to.
Oh my god I have said this to my ball-scratching husband so many times.