He can believe whatever he wants, and I certainly don't have a problem with it practically, especially with some SJW type woman who may just make shit up about you to further her mad-dog political beliefs.
What I don't like about it is putting a Christian spin on it. There's nothing in the Bible at all related to the idea you can't be alone with a woman who isn't your wife. Christians are supposed to have control over their sinful impulses through Christ, and to be it would strongly bring that into question if a man felt he could not sexually resist a woman one on one. Quite frankly that sort of dim view of humanity and supposition that all men are animals incapable of controlling themselves smacks of the Koran.
If you study western history, including how the laws worked in Europe for a long time up till recently and even in this country till about 50 years ago. A man being alone with a woman not related to him and not his wife was highly frowned on kind of for this very reason (and the same thing for an unmarried woman to be alone with a man not related to her). To have spent the day alone with an attractive woman not related / married to you was pretty much a guarantee that there would be endless gossip that you did something.
Now different Christian sects had/have it as doctrine/practice or didn't/don't. You'll find most everything over the years & to this day.
You'll also notice however Orthodox Jews follow an even stricter code of conduct for married men and women not their wives / relations
(But strangely nobody seems to criticize them for it... now why is that?) No talking, no touching, no being in the same room alone etc.
Some Christians do follow the path that one should not only not do the sin, but avoid the appearance of the sin being a possibility, avoid situations where you would be tempted to sin, and avoid putting themselves in a position where one could sin. I can find no specific fault in that. You'll find many follow that path or at least respect it.
Much like if you don't do drugs... well someone you know comes and says, hey come hang out at our brand new drug den to celebrate the legalization of weed, just hang, you don't have to smoke, and you can just talk and catch up. So you say... thanks, but if you want to hang out, how about the park or the movies not your drug den, I don't want to be around places where drug taking may happen or have any appearance that I was at a place where it may occur.
Many other cultures in the east also had strict rules about who hangs out alone with women that are not their wives.
This is not a new issue, it's just new in that we haven't been used to people being so brazen / shameless / flaunting their lies before and all the communists egging them on and then covering up for their lies.
(It used to be if you made allegations that were proven untrue, you were shamed enough to have to permanently get out of town at the least).
Yes the Muslims also do it to, and there again in varies by region from the crazed fanatics in Saudi beating people over it and torturing them, to places more moderate like Iran where you simply sign a 30 day "marriage" contract paper be it for a couple hours or a couple weeks and hang out as you wish. Then when done, no problem walk away.