At the moment, games trying to get the best visual quality avoid geometry shaders. Usually you get more performance via other methods. This could change in the future as GPUs/drivers change, but for now geometry shaders have issues.
Because of this, and because raw compute power can sometimes be limited by the .NET runtime (array bounds checks, lack of full SIMD coverage etc) I would love to see a very nice API for using compute shaders. For instance, the fastest I can do perlin noise in C# is ~5x slower than I can do with C++, due to SIMD limitations in System.Numerics. With a compute shader I could do it ~1000 times faster than in C++. Anyone doing procedural generation at runtime could benefit from nice compute shader support.
I assume at the moment you could just use opentk to do compute shaders though, yes?