Just because a "wrestler" is a wrestler doesn't mean he will "only" wrestle if he were to step into a ufc ring.
He can take someone down and rather than just try to pin them start smashing his fist into the side of opponents face now .

He no longer has the "no chocking rule" now he can wrap that big arm around the opponents neck and choke them until they collapse .

The upper body strength of well conditioned males is far beyond what a female can muster.
Many ju jitsu moves still take a lot of strength to pull off -I've seen many strong wrestlers use their strength to get out of arm bars and other submission holds.

Look up fallon fox transgender ufc fighter Rhonda declined to fight him -plain and simple reason -she knew she'd get her butt handed to her.