The issue would be that a 5th Gen could have come already 10 years ago. It's pretty late for that, especially for a country that doesn't field any other low observable aircraft. So developing a 5th generation fighter in the 2030s may not be the smartest decision for a country like France, which all things considered still holds regional power ambitions.
For context, the capability France would establish in the 2030s already exists in the UK and Italy for a while, with Japan joining in and the US and China obviously being ahead in that regard (counting China here as ahead, due to Fujian being arguably the most capable carrier outside of the USN, the J-35s have yet to make their debut on it).
The idea in Europe was to sell Eurofighter and Rafale as capable alternatives to advanced F-15s and Flankers. Skipping the fifth generation due to budgetary reasons and the overall low militarization in Europe post cold war until pretty much now. Then the decision was made to band together (in two different programs respectively) and pool money and resources to then develop a sixth generation jet. And such an aircraft would grant France the only carrier capable 6th Gen outside of the US and China. A state of the art, cutting edge, networked stealth fighter with the associated subsystems and drone support of the next generation.
By comparison, something that the F-35C is doing since 2019, and the J-35 is about to do now, just isn't the leap in capability or achievement that one would expect from France in the 2030s. It's essentially admitting defeat, being now in the same class of countries like Turkey or South Korea, rather than a serious alternative to American or Chinese systems.