How big a girth do you have? I'm sure if you found a cock hungry bottom, it really doesn't matter how thick you are.
To me, a guy's ass is snug, but not really tighter. I think because a woman has a vagina, there is a bit more room to expand inside. But I've had guys who were very much into anal and their asses were very open and "forgiving" to what ever type of assault I was going to give it.
Of the women I've had anal with, once I'm in, then it seems to open up just right and stays about the same no matter how much fucking we do.
Note: I've had anal with 20 women and 70+ men