C# is basically a "Microsoft Java". They tried this already with J# and their own runtime, but then got sued and decided to make their own JVM but this time with blackjack... and hookers.
Microsoft Java makes it sound likes it's an inferior clone. Rather C# is Java reinvented with the benefit of hindsight, and improved with new concepts and sound language design from there.
Both languages have a too enterprisey ecosystem for my taste, but when given the choice between Java and C# I would take C# every time. Though modern Java certainly made efforts to catch up again.
I'm just guessing based on language similarities between the two