The members of HUNTR/X — the fictional K-pop group made up of nonfictional singers EJAE, Audrey Nuna and REI AMI — have just become the first women K-pop artists ever to hit No. 1.

In 2018, Mitski released her fifth album, Be the Cowboy. She had been putting out music that was as critically acclaimed as anything in the American indie world, and promoting it in the only way that ...