virtual thread instead of async/await is a counter example.

Java is more used than C#, they can wait before delivering a new feature (given their leader position) but cannot deliver a flawed implementation that would stay in the language forever. Glad to have virtual threads and the backward compatibility that comes with it instead a Async version of sync methods + async and await keywords all over the code and Task as a return type in my interfaces methods to allow implementations to do non blocking I/O calls if they need.

I use Java and C# and appreciate them both.

C# did not ship with async/await, and Java didn't have virtual threads back then. I am specifically referring to the initial choices made in C#'s foundation.