The R GIS ecosystem has seen great strides recently! I've just been working on one part of it: 3D visualization and computational hillshading/raytracing.
And that video looks like a great resource--I'll put it on my watch list.
You should check out Mapdeck [0]. It's R bindings to deck.gl, a JS 2D/3D geo-visualization package that I've been contributing to. As of version 8.1, there's a TerrainLayer [1] to render an interactive map with a 3D terrain mesh.
And that video looks like a great resource--I'll put it on my watch list.