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First thing to note, is that basically nobody uses the hash function it describes. Second thing, is that the other two claims specifically discuss 3D or higher. What I take from this, is that 2D Simplex is not and has never been covered by this patent. I am also not aware of any other that does cover it. Even in Ken's paper on Simplex noise, he never mentioned 2D noise. Whether he knew a source for 2D triangular gradient noise before this, or he just thought it was too obvious, is something I can't say for sure. In FastNoiseLite, the 2D noise used by the OpenSimplex2 option is an actual 2D Simplex implementation, with nothing special except for a good gradient table. This code comment clarifies this, although you do have to dig to find it.
Several years ago when I was experimenting with all of this I found that OpenSimplex was significantly slower than regular Simplex (not sure what library I was using). Maybe it's improved since then? Anyway, I've since moved my noise computation to the GPU and speed is less of an issue for that particular project. I'm currently using the simplex noise function from GLM, which comes from https://github.com/ashima/webgl-noise. Do you have any idea how that compares with the various noise functions you've listed?
Re: GLSL noise, I have GLSL implementations of the 3D cases here: https://github.com/KdotJPG/OpenSimplex2/tree/master/glsl . There are certainly a number of optimizations that can be done, especially simplifying the gradient vector generator, but they do work.