For a boycott to be effective, it helps to be relevant.
Personally, I didn’t like Elvis Costello when he was relevant. In the early 80s, the music industry was trying to push “geek” rock on us (Devo, Talking Heads, Elvis Costello, etc). Elvis Costello was the worst of it...nasal voice, poor instrumentals, uninspiring lyrics.
He was considered one of the best lyricists around.