After 24 years, polka has had its last dance at the Grammys. The Recording Academy, which bestows the Grammy Awards, announced late on Wednesday that the polka category would be eliminated, saying in a statement that it had been cut “to ensure the awards process remains representative of the current musical landscape.” To many in the polka world, that read as a kind of industry code meaning that their genre — once capable of supporting artists with million-selling hits, but long since relegated to micro-niche status — had slipped off the mainstream radar entirely. “It’s devastating,” said Carl Finch of...