In organized sports like wrestling, a woman will be at a disadvantage because she will have a slightly higher percentage of body fat, which means she will have slightly less muscle. However, particularly in the lower weight classes, this disadvantage can be overcome with skill and fighting spirit.
I'm 46 and weigh 160 lbs. I work a 50-60 hour week, mostly sedentary. I run & lift weights, but am in no way a serious athlete. If I had to go in the ring with one of our women's judo olympic competitors, she could play with me as long as she felt like & finish me off at will - I wouldn't stand a chance.
That doesn't mean martial arts are an end all for women - after all, few women are serious athletes either. Fortunately, neither is the average thug. And the average thug isn't looking for someone he can beat after a 15 minute brawl. A woman who knows how to throw a real punch, or one who knows how to escape from a headlock/twisted arm, has a much better chance of escaping than someone who knows nothing. Unfortunately, most MAs are taught in McDojos where the woman is taught she is invincible - a real bad idea since size counts. There is a reason why there are weight classes in judo, boxing, etc.
As for wrestling, I'm on the side of "Let 'em try". Most will not be able to compete. Those that can are welcome to. Nor would I look down on a 130 lb boy who lost to a 130 lb girl - she may be only a few pounds lighter in muscle mass, and know more technique.
Women in combat - I'm opposed. The number of women who can pull their own weight isn't high enough to justify the effort, and there are too many sexual problems brought with them.
That"false" sense of security will go far to protect a woman on the street. She radiates confidence and that will deter most assailants alone.Skill with a piece and carrying is the gold standard, though.
Reality is martial arts will only give the female a false sense of security, a 105 lb female will be no match for a 250 lb assailant.