The F-35 is around 6-8 years late, depending on who's IOC you are referring to - I recall USMC moved from 2008 to 2010, to 2012, and finally to 2015.
The cost is, alas, high in almost ALL early aircraft development stages but, for F-35, they are already tapering towards the approx. $80-90M per aircraft (F-35A) forecast for Full Rate Production from 2019+. Sustainment costs are key though.
Have costs been allowed to spiral beyond reasonable limits in the not-too-distant past? Yessir! There's a scar of Nunn-McCurdy that will never fade, buuuut, the Program is way beyond any fallacious cutting off of noses to spite faces.