Similar to existing
collada tags, would others be open to creating a 'gltf' tag? See https://www.khronos.org/gltf/ for format details. It's a relatively new format, but there are currently ~40 questions mentioning glTF, and ~5 in the last month. If those 40 were tagged, it would be a roughly average popularity tag for this site.
Disclaimer — I'm part of the Khronos Group and help to maintain the glTF format. I'd like to use the tag to watch for new posts so I can answer questions and handle any bugs. I don't have 300 reputation, and cannot create tags.