The implication seems to be (in its nicest terms), NOT that Ms. Griner is a man, but that her gene pool has given her an advantage over most women. Her voice and her physical abilities have given some a chance to describe what she has done as only natural for someone who is very close to being, but not quite, a man.
There is an ugliness in this type of attack that makes it hard to put into words just how good Ms. Griner plays basketball. There's a minefield that awaits any comparison between Britney Griner and, say, Ralph Sampson. But there is no woman who compares to Griner.
Conundrum is an apt term for the problems people have when they try to describe the wonderful play of Griner without offending either her or someone else. Muffett McGraw stepped into the minefield. She didn't mean to, but there she is.
Man, if your Mom made you wear that color when you were a baby, and you're still wearing it, it's time to grow up!