If anyone said this, they are very wrong. If they heard of Flex, this means that they had some interaction with enterprise apps, which means that he should inform more and maybe ask himself a question: why banks or corporations are still hiring flex developers even after the Adobe’s announcement?
Flex Framework continues to be one of the best solutions for targeting your application cross-platform on mobile devices or PC, depending on your project’s requirements. And the future looks bright, with Spoon Project and the long way possibility of using FalconJS cross-compiler.