I think the misunderstanding of the word "traditional" may be the issue. Granted, glass bedding has a "tradition" amongst some 20th and 21st century stockers and builders. Much in the same way that some modern bowyers consider fiberglass backing a bow to be "traditional" because it goes back to the mid 1900's.
With that said it should be pointed out that traditionally all guns from pre-rev right through the early 1900's were made of 3 things, wood, iron, and brass. In the same way all bows prior to that point were made of solely, or combinations of wood, horn, sinew and baleen. That "tradition" still stands and is practiced by some today.
I do not however see the use of artificial lighting, modern barrels and machined locks as a modernization of the art, provided we stick to the "tradition" of building with wood, brass, and iron in "traditional" manners.