All military aircraft are maintenance nightmares. They're also extraordinarily loud and devour fuel. These are not intended to entire commercial service where they need to turn a profit for the operators.
The F-35s train over my house. When the business end of the engine points downward it rattles the windows and sounds like freedom.
> They're also extraordinarily loud and devour fuel.
Steal helicopters have entered the chat.
Maintenance is an issue for more than just profitability. More maintenance means fewer sorties in a given time period, heavier reliance on and utilization of supply chains, and fewer platforms that can be serviced by a given set of mechanics and facilities.
Just look at WW2: Germany had some fantastic equipment, but they couldn't field it because they didn't have the fuel, spare parts and the maintenance capabilities available. A tiger could kill 10 Shermans, but the Americans could always bring up an 11th Sherman.
For decades we have been able to afford complacency - we strike when we're ready against people who mostly can't strike back. We can afford to be wasteful because we have so much more than anyone we would go up against. No one is seriously threatening our ability to keep our military going. But militaries need to be prepared for peer conflicts where someone could give us a run for our money.