Okay, now I am really skeptical. You're claiming that France's decline in population growth reflects Malthusian limits, but also that rural life was better in France than in many other places. And there was no rush to French cities the way there was elsewhere.
Why didn't France have this massive advance?
What? I'm not talking about Malthusian limits, I'm talking about employment limits and said so a bunch of frigging times - if additional labour isn't going to increase the yield/value of a plot of land that labour isn't going to get paid/fed even the the land is producing sufficient calories to feed that labour.
In France, the employment limit was approached more smoothly and having lots of children was disincentivised relative to other locations. Working population (P) was less than the employment limit both before (E1) and after (E2) the agricultural revolution.
In other European locales the agricultural revolution - enclosure, much bigger farms, better crop rotation, mechanization, infrastructure, potatoes, winter wheat saw a shift faster than peoples demographic adjustment where it was found E2 < P < E1. The amount by which P < E2 had to leave the rural locales and move to the cities/abroad in a massive surge.
Since they were economically unstable during and just prior to these migrations they had lots of kids (which is always a safe bet when times are uncertain). The new urban populations were also quite fecund as it was advantagous to be so when labour was non-skilled. In rural France you'd need less kids to secure your farm and old age, and since the farm labour was more skill intensive each child is addition costs - so in the absence of cultural incentives to lots of children people try as hard. This meant rural growth was slow and there were no new urban cohorts to push growth.
The reason why E2 << P in some countries and E2 < or = P in France was because non-mountainous France had better infrastructure and farm structure to begin with (so the gain was less), a differing agricultural base, the new crops provided more gain in places other than France, energy in France was more expensive (due to lack of coal, renewable woods, and the distance needed to transport to the ports).