So it comes out of box with good renderers, physics engines, localization, input controllers and in-game GUIs?
As for the generic things, I think C# is the only mainstream language which has small vectors, 3x2 and 4x4 matrices, and quaternions in the standard library.
They've got SIMD-accelerated methods for calculating 3d projection matrices. No other ecosystem is even close once you start digging into the details.
If you're willing to constrain yourself to 2D games, and exclude physics engines (assume you just use one of the Box2D bindings) and also UI (2D gamedevs tend to make their own UI systems anyway)... Then your best bet in the C# world is Monogame (https://monogame.net/), which has lots of successful titles shipped on desktop and console (Stardew Valley, Celeste)
Depends. There is Godot Script. Seeing how it comes with a game engine.
But original claim was
> actually dotnet also does not need too many dependencies for games and desktop apps.
But general purpose programming language has very little to gain from including a niche library even if it's the best in business. Imagine if C++ shipped with Unreal.
Are you really trying to compare serde to rendering engines?