This is a nice idea in an ideal world. Unfortunately, it ignores the fact that we live in THIS world, where lobbies will react even before the bill can rack up a dozen co-sponsors.
While the label for GMO products is being considered, there will be intense lobbying to rename a certain kind of GMO as "selectively-bred enhanced produce," which will then not have to carry the label as it is not really GMO. It is "selectively-bred." The onus will be on small farmers to prove their produce is not GMO, which many will suddenly find is impossible due to years of cross-pollenation. Certain larger processed food companies will not have this issue as their produce is "selectively-bred," and they have decades of records demonstrating how their product is SBEP under the new guidelines. No label is required, but "SBEP" must appear on the ingredients list somewhere in teeny print, accompanying the item that the SBEP produce/grain was used in.
Get where this is going?