International Chess Federation (FIDE) to ban and punish transgender players
(www.erininthemorning.com)
you think people who are biologically male have an advantage in mental only competition
They do. There are two types of chess competition: open and women only. Women don't do well in the open competition which is why they added the women only competition.
But it's not because men on average have an advantage. It's because men have a greater spread of chess ability so the very top men tend to do better than the top women.