Newish low level features of C#: https://em-tg.github.io/csborrow/
Now, I understand that you may talk about it from a non-technical perspective, but even so, there are major differences. C# is a general purpose language for the cloud/web, and so is Go, but Go is also widely used in other areas like in embeded software. TinyGo is soooooooo much better than working with C/C++ or Rust as an example. Places like that where you wouldn't usually find a transpiled language (other than maybe Python with MicroPython).
Also, check out nanoFramework for a .NET runtime that can run on MCUs like the ESP32 [1]
C# is more expressive and .NET comes with batteries included. Go is more explicit and more verbose.
You can pick up Go faster and is easier to reason about Go code when you first encounter a new project but C# feels like it enables you to develop faster and be more productive.
For web both are excellent and performant, even if they have different philosophy.
What I like about C# is that it becomes more functional and I can even mix F# in the projects if I want even more functional programming.
I worked with C# for a decade, I'll likely never work with it again if I can help it. Not because it's bad, it's better than it's ever been. But because I really dislike the way they include their batteries. It leads to long debugging and refactoring sessions when tired people have written what is not their best work on years worth of thursday afternoons. I think people who like implicit frameworks must have been good enough to work in places that had better quality than the places I've worked.
Currently my favourite way to build applications (desktop or mobile) is Kotlin and Compose.
I never used Dart, how would you compare it to Kotlin ?