It will be interesting to see how this plays out. Spotify announced that it would start to crack down on adblockers in 2019 [1], but I've been using ublock origin on their web player since then and haven't noticed any issues (apart from the odd glitch when the blocker is trying to skip the ad). Did they get cold feet or was it mostly a PR move?
Sometimes it's just for the scentiment. For example, YouTube has had a policy since 2015 that you can't have third-party brand logos in your videos unless that brand also buys out all of YouTube's banner and in-video Ads in the video, and it couldn't be a pre-recorded ad, it had to be a sponsor spot integrated into the content. Supposedly there was no outrage and this policy stayed in place, and was just never enforced. https://youtu.be/t17PVwreKEE?t=93
https://gizmodo.com/spotify-may-suspend-your-account-if-it-c...