I wonder whether it isn't actually a good thing that mothers are fearful their sons could be falsely accused of rape or being perceived as potential rapists.
It is parents' role to teach and demonstrate to their sons the risks if they fail to ensure they have obtained real and conscious consent from their partner when engaging in sex. And indeed help to educate them, how women feel vulnerable around strangers, teaching them to respect others rights and vulnerabilities is important.
Why an earth would any mother want to not discourage their son from sexually predatory behaviour or scenarios where their behaviour could be considered as opportunist and risk a 'false' accusation of rape.
In most scenarios of 'false accusations' of rape, the accuser is often a vulnerable woman or someone who regrets her choices the next day. Would you really want your DS's to have a sexual encounter where their partner feels like that the next day?
These were all discussions I had with my own DS as he was growing up. I didn't make a big deal out of it, just had a chat about it when the scenario came up in the news or in a film. Equally you can damage a son's attitude to conscious consent by negatively blaming the female in such scenarios in front of him.
FFs stop feeling sorry for the poor boys, having a penis is no excuse for stupidity.