Another recent cool work in this field is this paper : https://repo-sam.inria.fr/fungraph/3d-gaussian-splatting/
They manage to get the same quality, with <1hr of training, and running at 60fps 1080p, it uses point cloud instead of volumetric representation
I'm anxiously waiting for the code (or for someone to reimplement it open source). Sounds very fun to play with.
I've recently been having fun with OpenMVS [1]. Using Gaussian splatting (which is initialized with a point cloud) would bring it to the next level!