Girls are generally weaker than guys. It might not always hold true but most guys can often underestimate their own power and hit harder than expected.
Sure, I'll punch guys as a joke, on the arm or whatever, but it literally never hurts them. Guys have punched me before, as a joke, in the same way, thinking they're hitting me as hard as they hit me, but it's often painful as fuck, and i'm left with a bruise and my eyes get all watery.
I don't even think men & women can be equal. We're superior to each other in different ways so being equal is impossible.
I reckon that women are generally treated with more respect by decent men because we're the reason the human race continues as it does. Think about it. You exist because of your mother, a woman. Your mother exists because of her mother who exists because of her mother, and so on, all the way back to the beginning of humans. Humanity owes everything it has to the women of the world.