It's a non-issue for most French people like myself. In France, the Tesla cars are in the luxury price segment. There's no need to incentive the car that only wealthy people can afford.
You need to have income, but you can get a car on a bluecollar salary, and an incentive of 10% on the price is significant.
If you're actually wealthy you'll want to buy a bigger car, and the same incentive is both less significant and less useful.
I don't mean to claim that anyone who buys a new car is financially independent.
Then again Tesla is not hurting, they sell just about everything they can build.