Read what you said. "not believing a guy and trusting what he said is unfair?" Sorry, but rapist lie and present themselves as trustworthy. The same as thiefs. They won't tell you. But until they act, you don't know what they are. The problem is that if a woman trust a man and that man happens to be a rapist, men (and some women) are quick to judge her and say "why did you trust him? why did you believe him?"
You claim that men provide protection and that is what men do best. But I suggest you read the stats about girls and women who have been raped. Because those numbers are high. And that means that "protection" is failing a lot.
If protection is what men do best, explain how it is possible that such protection fails 25% of the time in cases of rape and even more when it is just "abuse" like being gropped. Oh, and usually "protection" means telling women how to wear and that they should stay home. As if the ones who have commited a crime and should do punishment (house arrestment) were the women.
Sorry, but until "protection" works in a way that women can trust men without taking a risk of being raped, that protection is not working. Until a woman can trust men like men trust other men and remain safe while doing so, protection is not working. And that is based on results and data.
I'm going to trust that most men would want protection to work better and that the lack of results is due to men being trustworthy of other men who might not be as nice as men think they are. At least not to women. But the fact remain, women are groped, abused, raped and killed in a high rate. Since protection doesn't really work, they are told things that they should do or don't do to "remain safe" and attacked if they are not careful enough. Even with all the precautions, the predators among men, still manage to gain their trust by lying and pretending and still hurt women. And when that happens, for some reason, the protector among men, don't punish those men. Example: you have a rapist as president of US. He would abuse and rape again. Men have failed to protect the future victims of that president.
You talk about red flags and creating safe spaces, but right now, the whole USA is unsafe for women. And men are ignoring a whole parade of red flags for women. If fact they are shoving those red flags in their faces and telling them that they have to "deal with it and just suck it".
So if men are really The best at protecting", I would like to see results that prove it.