I also like Java, but c'mon no decent algorithms being implemented in C#? That is already approaching zealotry.
In C# the solution is half baked or archived or abuses allocation.
I think Unity has way more with C# adoption in game dev than innate C# qualities.
Sure you could use YAML parser, but it allocates everyone and their mother. Can you find a Fluent localization in C#? Sure, but its outdated and archived. Ok, but basic RoaringBitmap implementation? The repo is archived and not fully complete.
Why C# is used in game dev is incidental. It has more to do with Unity and XNA/FNA than any concrete quality of language modulo value types (but then again, most C# libraries don't focus on avoiding allocation and are just as happy as Java to construct a complicated hierarchy of classes).
Want a fastest possible library? It's in C++, and not portable to Win/Mac. So good luck with wrap + porting it.
Want a decent implementation of an algo? It usually exists for Java but not for C#. Hope you like writing it from scratch.
Want a C# implementation of an algo that doesn't allocate to the Nth degree. Again, write it yourself.
But ok, maybe Unity has a good ecosystem... And they fucked it over a barrel.