I used to paint old masters portraits as a hobby (including Rembrandt). I think it's a bit disingenuous to describe this as 'painting'. On top of ma2rten's criticism that it basically photoshopped previous examples to create a most representative work, I'd add that 3D printing with texture is not painting. Rembrandt, in particular, was known for painting with countless layers of semi transparent glazes to give his paintings a sense of depth and an ethereal glow. He'd also mix his pigments with bindings aside from pure linseed oil, sometimes adding chalk or glass. 3D printing the final result with none of that process makes for a very limited reproduction.

Also, I'll add that I think it's very impressive, but I think they're overselling it here.