This is true, although in slight compensation, there is a true culture of dissent. It is common in the US to have to be an all-in cheerleader for whatever the current project is, until it fails, then everyone dusts themself off and hops back on. French people are quite bad at the dusting-off, but they also don't usually let their colleagues attempt to win a horse race while mounted on a pony.
Because French engineers are also more educated on average than US engineers, and French school ratings more predictive of the IQ of their incoming crop than of their "leadership" or whatever the current US proxy for socioeconomic status is, having a minority of French engineers in a team to point out obvious points of failures can be a definite advantage.
Personally I prefer American managers though, I feel the can-do culture is just better for management. Plus French people tend to have a lot of respect for older people or people further up in the hierarchy so in a mixed hierarchy (with the Americans at the top) usually your French guys will move towards becoming self-starters in their bosses' images, whereas the reverse is not necessarily true and American underlings tend to perceive a French boss's nitpicking or challenging of their strategy as micromanagement and undermining.
I think this last part is one of the great remaining challenges of France as a nation of great enterprise. It is very, very difficult for non-French people to feel comfortable in a company born of French senior management and culture. They just don't get some of the tone and French management can be very backwards compared to the commonly accepted leadership forms today. Hopefully, French children today are seeing a very different picture of what it means to be in charge thanks to exchange programs, higher education and a greater involvement from the EU, and they will grow to be leaders who are not afraid of hiring whole teams from other countries and letting them have autonomy and who do not make their teams afraid of them.