In its official announcement, the USFWS explained it was removing the hunting element requirement from future Duck Stamp art submissions, beginning with the 2022 Federal Duck Stamp Contest. The USFWS also changed the contest judging requirement mandating that judges have an understanding of America’s waterfowling heritage, and the ability to recognize objects related to waterfowl hunting.
When asked why, the USFWS cited broad dissatisfaction among artists, and a desire to broaden and diversify the stamp' appeal. For more on the story, check out Brian McCombie's story over on the nrahlf.org.