> How .net got so many things right where java did not is a mystery to me

Part of the reason for that is that Java is older. https://en.wikipedia.org/wiki/C_Sharp_(programming_language)...:

“In interviews and technical papers, he has stated that flaws in most major programming languages (e.g. C++, Java, Delphi, and Smalltalk) drove the fundamentals of the Common Language Runtime (CLR), which, in turn, drove the design of the C# language.”

Also, some of Java’s design warts may be there because Java was initially envisioned for much smaller devices.