so i did this. got the link saturday morning and downloaded all the zip files provided. the “Store Re-download and Update History.csv” buried in the app store -> account and transaction history was the most concerning. discovered a number of songs purchased from the itunes store years ago were being repeatedly downloaded to my watch. got on twitter with @applesupport who ultimately bailed on my query, telling me to contact the senior advisor who’s been taking care of my watch playlist bug.
i’d discovered previously my phone loading tracks that weren’t in the playlist and playing them. then i’d find they hadn’t shown up in the previously played list (ie: not being marked as played). rooting through the file was the evidence that i hadn’t been hallucinating: that’s exactly what happened.
i’ve stopping music from apple since there doesn’t appear to be any way of controlling this unwanted behaviour. unfortunately i’m stuck with having to trust itunes/apple to not mangle my third party downloads and ripped cds.
btw: i’ve got every visible toggle on every device regarding automatic downloads turned off. i also don’t subscribe to apple music or itunes match.