The whole valley has been filled with top french engineers for 40 years. This brain drain is actually one of the reason france is in such a miserable state relative to IT economy. The only ones left are the ones prefering a cosy seat at a large established company. All the entrepreneurs have been leaving, and it’s a misery (another example under the spotlight now, although in a different field, is the head of moderna).
I have a friend from France who has a successful career in software (making good money in the United States).
His parents are kind of disappointed in my friend, though, because they don't believe his career is a "real job" (like a lawyer, doctor, financier etc.).
I think this is a contributing factor to why people leave. "Software Engineer", for all our quibbles over what it means, is comparatively well-respected and well-compensated job in the US. People want to live and work where their skills are valued.
Worked along folks from EPFL, the X and Poly. What they told me about their startup ecosystem back home was unbelievable. And compensation was a joke too.
Are French folks... aware their smartest are in California?
* France (and other French speaking countries) produce well qualified engineers.
* As others have pointed out, France can be perceived as a rather inhospitable place for entrepreneurial people.
* On the other hand, Apple may be a little bit more aligned with French values than other Silicon Valley companies: Pride of auteurship, opinionated design, and occasional stubbornness in the face of customer complaints. I think a French engineer will recognize a certain je ne sais quoi in "you're holding it wrong" ;-)