Couple ways to think about it. If you stop buying now the cost goes up exponentially. The reason the cost has come down to something reasonable for the capability is because of rate. Huge push to sell internationally which will also drive down costs. The capability is needed. Don't care what the news says, it works, and it works well. Cost to fly are to expensive, but that also has to do with how the USAF and Navy are using it. Costs are going down.
It has always been known that there will be a need for 4th gen fighters. LO fighters open the door. Day X afterwards is everyone participates. An AC-130 isn't diving into a China scenario until there is some type of Air Superiority established, be that a specific opening and closing of a land mass, or total air superiority.
All fighters are trucks to carry weapons. We have limited trucks (Desert Storm 147 Fighter Squadrons now approx 54 on a good day) and need improved weapons. The weapons that the F35 carry are 3rd gen with a few 4th get weapons. How did we get there? the USAF and Navy didn't buy new stuff.
Force structure was discussed by the Chief of Staff of the Air Force yesterday at the AFA conference. He wants a new force presentation model to combatant commands which will lead to different mixes of aircraft and personnel on a predictable schedule. Wargaming has shown a need for a mix of aircraft to get the job done.
Do some research on the parts that make up the cost of the F35. It is open source, and eye opening.