It's Euclideon. And it is octtrees. My interpretation after reading a fascinating Reddit thread [1] is that these denials were misdirection. There's definitely new interest in splatting techniques (Gaussian in particular), though they've long been an alternative to triangles in the 3D world. I think it'd be fun to experiment with implementing some of that using modern compute shaders.

[1]: https://www.reddit.com/r/VoxelGameDev/comments/1bz5vvy/a_sma...