Many airlines are carrying less pax but FR are carrying more but at a lot lower fare. If fares are 20% lower then you need 25% more pax to get the same income. It costs more to carry 25% more pax. The airline has gone well below the optimal price point to make money. It need to fund a few billion euros of new planes but has static income. As a business it is easyjet that has got things right and kept growth low so that fares are not undermined.
Don't need to drive income hard when your costs are falling.
As for needing the income for new planes well think the €200 plus million cash generated in Q1 goes towards that quite nicely.