I have to say I disagree mostly with what you say. The earliest versions of auto wipers were marginal at best and if I used them I had to intervene constantly to get satisfactorily results. Now the recent version that is supposedly ML trained I find is not perfect but equal to or slightly better than those I had in two Mercedes and one Hyundai. According to what I read if you have to get them to swipe manually that goes into the data set to improve performance. I have not had chattering issues except occasionally on our MX but not on the M3. Note rainX or other lubricants plus worn blades can be major causes of this. Also to be transparent I have used the new auto wipers on both our cars for rain and snow extensively since the last two releases came out in Dec - we live in Truckee CA and I work in the valley.Just had a chance today to confirm my previous suspicion. In this case there was absolutely no rain, only spray from the car in front.
This would be the same in light rain that would be light enough not to trigger the sensor. In this situation anyone would get frustrated simply because we can't tell whether the droplets are from the sky or the car in front, and assume it's raining that hard and the sensor does not see it or it's very slow to respond. I think this is a design flaw not of the car but of the "Auto" feature of the wipers. It simply does not have a good enough sample of the windshield to make a good decision.
I tried to record the area near the camera, it's not very obvious, but it's mostly free of any water drops, obviously not enough anyway to trigger the wipers.