I think this little problem of age discrimination has many different origins. It supposedly got going back about 50 years ago when the then-head of American Airlines needed a stroppy group of older pilots sorted out, so that he had a quiet word with his friend the head of the FAA. No sooner said than done: we got the 'Age 60 Rule.' Things were much simpler in those days, of course. In the context of the times this was not seen as anything grossly out of order.
Here and now it's not really helpful to blame the French, per se, for what's going on. Some EU countries are more responsive to pressure from special interest groups than others. Germany, for instance, changed their laws on the conversion of foreign licenses after some bleating from 'Cockpit' about Yankees coming to take their jobs. Well, that's the explanation I got from a friend who pays for his haircuts by the number of sides shorn, so...
Compared to working for a living, working in aviation is still a pretty good deal. If I cannot get this or that job due to my DOB, well, tough. And if some snivelling little sh1te wants to gloat about how his way into that left seat shall be made smooth by having the incumbents taken out behind the hangar and shot, so to speak, let that just speak to the class of such a person. Hey, maybe they need that way to get ahead! This is not going to be my problem.
Take the Positivist approach. Every morning you look into the shaving mirror and repeat, 'Every day in every way, I am getting better and better.' Some Frenchman thought this one up, I believe, but what the heck.