The process depicted in the video is a variant of Stereolithography a process by which photopolymer is solidified by exposure to directed UV light. The video depicts the authors using a commercial 3D printer created by Digital Wax Systems. Reading the paper, it appears that they mixed in amorphous silica to the resin and ran the printer successfully. Few details are given on their test rig.

This approach has been applied successfully to create ceramics in the past, and doesn't seem particularly novel to me. Companies such as ADMATEK are already commercializing this technology.

Weaknesses of this approach are that the end part needs high temperature sintering to remove the photopolymer from the part, and will not yield the same material properties as monolithic glass. Significant shrinkage can be expected and the sintering process means that you are limited in the thickness of the parts that can be designed.

All in all, this is a nice note, but isn't fundamentally introducing a revolution in the 3D printing space.