I don't think we'll get to not having enough food, at least not in the West, the problem is getting food to countries that are the most affected by this. One idea is to suspend the EU's plan for reducing food production (due to previous overproduction that crashed the prices).
As for his proposal of food vouchers, it's a campaign proposal as the election is in 3 weeks. In France we already have money handouts to the poor, unemployed etc., with one criticism of the system that it can be abused, you can do anything with the money, so I think he's trying his usual "two birds, one stone" approach, offering more help to the poorest, but ensuring that help will really go to food.
So the usual famine and wars in Africa, South America. India? But to middle class, you might have a small problem with the distribution of wealth when you need to provide food vouchers to middle class
There would be NO 'middle class' in a situation that resembles "Soylent Green".
Do I seriously think that we are going there?
Hopefully, not, but the food availability implications of the current war are a bit unnerving.