Last time I checked no one was trying to convince the French to buy F-35.
It's not an endless black hole. The airplane has over 1000 hours of flight test on it. Previous cost estimates have all been based on powerpoint, but current estimates are based on the real world and a growing body of evidence. So they're becoming higher fidelity and increasingly believable.
If you want to take your flight of Rafales into an S-400 missile engagement zone (
S-400 SA-20 Triumf - Russia / Soviet Nuclear Forces if you don't understand the buzzword) alone and unafraid, crack on. I'd rather be in an F-35 thanks very much.
A British MP rather famously pronounced the demise of manned fighters in 1957. Fifty+ years later, we're still waiting.
Regards,
Single Seat, Single Engine, The Only Way To Fly