"French doctrine"
Is this a joke ?
Yes, France have multiple different doctrines. It's most known one is the "Force de Frappe" [0], but the Legion have one, and if you talk about "doctrine d'emploi" every bit of equipment have one (the AMX-10 necessitate a doctrine d'emploi so different than regular MBT than the whole French cavalry have a different general doctrine than any other mechanized troups)
I don't think that's true. As an example, Finland and French doctrine are very different. It's easier to test all Euopean nations diffrent doctrine and choose what works best (especially if countries from the Balkans add their grain of salt)
Imho that's where European defense industry (as a whole) is interesting. Because you have 5 competing IFV designs (well, over 15, but really, 5 different design that does different things). You also have multiple tanks (and AMX-10s), as well as a bunch of different drone constructors. Even in gun design you have multiple choices, andh while optics and optrionics are Thales', overall equipements are extremely distributed. Europe might find itself on the backfoot in case of an engagement, but i'm pretty sure it would bounce back quickly.