There is also a healthy fear of change in the java community that could explain it.
Nice jab at the end! Java (well, really Sun, then Oracle) prioritises backwards compatibility over every other goal. So, does Win32 API. Does DotNet do the same? I'm unsure.This also explains why it took so long for Java to get lambdas. And, generics with primitive types, e.g., ArrayList<int>, via Project Valhalla. It is a super hard problem to upgrade Java without breaking old stuff. Hence, it is a multi-year R&D effort.