No, I'm sorry but that is WRONG. In France that is not the case. My sons were born in France in 1982 and 1984 and once they were toddlers I frequently travelled alone with my sons.Never ever was any suggestion made that I needed permission to travel with MY children and I would never have given a thought to possible discrimination. Woe betide anyone who had even inferred that I needed permission, permission from my husband, you are joking!
In fact if he had ever given me such a paper, I am just trying to think what I would have done with it, but something terrible to it and to him. I am enraged that you are implying that your wife is singled out as being unfit /unable to be allowed to travel with her own children. This is disgusting and disgraceful.
I'll tell you something, if ever I saw a woman being treat in such a fashion by any official in France then I would intervene, I really would.
And don't sound so cheery as if this is a good thing. it isn't, it is repugnant and insulting to women.