As I said, Keynesianism is cynically adopted by politicians as a rationale for expanding state action. There is strong demand for academics to provide politicians with rationales for what they want to do, so there are people who do it. Austrian Economics correctly describes the state as a drain on society, so politicians don't support Austrian scholars.
I also don't know that it's correct to describe the Austrian School as having lost ground. There is more work being done and more scholars in the Austrian School than ever before, as well as more people studying it. There may have been a very brief period in the late 19th century when it was more prominent amongst academics.
Further, my disagreement is not simply over an opinion. You made a strong claim that Austrian Economics has been proven wrong. As it is a school of economic philosophy that rigorously deduces conclusions from first principles, such a proof could only come in two forms: 1) a demonstration of logical inconsistency, or 2) a clear example of an Austrian theory being violated in the real world. I'm unaware of either existing, as you seem to be.