An app that was going to make it on my list was Anesidora, which is a native macOS Pandora player which of all the many music streaming apps I've tested includi

An app that was going to make it on my list was Anesidora, which is a native macOS Pandora player which of all the many music streaming apps I've tested including Apple Music, is the only one which uses less than 10% CPU total including on WindowServer and coreaudiod. Unfortunately since I got it the author seems to have removed it from the app store. There's some other native Pandora apps that might have low resource usage but I haven't tested them. I switched to Pandora for my music streaming mainly because of Anesidora, and luckily I still have it downloaded. Anesidora still redraws when it's hidden, but only once every second, and it uses lower CPU itself and in coreaudiod than other players.