view this video. This has been discussed at nauseam on the forum. At about 2:30 the BMW M engineer clearly states that some noise is normal, however a permanent noise is not. Mine seems to be a lot like yours, and it is for sure permanent. Every time coming to stop... It's horrendous and embarrassing. The only time I can get it to stop is to do like 3-4 hard 60-70MPH to 0 aggressive stops. And I mean like aggressive to the point of getting ABS to kick in. The squeal will then stop for the remainder of that drive. But it's back again the next drive. I tried the wheel cleaner thing too, worked for a day. and I agree, thats not a viable solution for a 100k + flagship car.
i'll also add, somewhere recently on the forum someone mentioned that there was changes made to the 2023 models to address this. In my opinion if there was indeed a change in 2023 to address the brake squeal, that tells me BMW has a fix for it, and to some degree they acknowledge the issue is real, so much so they made a hardware change to mitigate it. To me, (im no attorney) it would seem that that in itself is clear evidence they know something isnt right, and should give owners of 2018-2022 models the option to receive the fix that the 2023 models got. (if there was indeed a change). Again, it came from the forum, and I believe it was a dealer service advisor who told this forum member this. and we all know dealer service advisors leave a lot to be desired when it comes to facts and knowledge about the car. Some are great, and very knowledgeable, but more times than not? They're just sales people and dont have a clue.