alt Hacker NewsJ# was the transition product to port J++ into .NET, I am quite sure.
Not only I was there on those years, my employer was a MSFT partner that got to test .NET before it was announced to the world, so that we could have our products as part of the announcement event in Portugal.
OpenJDK is cherry picked, Google only picks pieces of it, rather than full compatibility.
No idea what you are talking about. Google internally has a massive amount of code based on JDK 21, and the (amazing and completely transparent move) to JDK 25 is nearly complete.
That's the full OpenJDK @ Google, and it has been for a very long time.