I am the fifth person who ever posted in this thread and have been reading all the e-mail updates ever since.
I never dared to update my iOS because I was afraid the problems might get worse. The downside of that is that Apple won't help you if you don't update. I am now running 17.2.1. It hasn't gotten better or worse.
I talked to an amazing senior Apple engineer this week. He called me back twice and we ran two tests/logs and sent them to him. He and some other engineers are now looking into it. What I did was this: I wrote down the EXACT moments in time when the sounds started to mess up in my car using bluetooth. He said that will be very helpful when inspecting the logs that I sent to him the following day. Maybe we should all try to have the same thing done. This way the senior engineers etc. have a better shot at localising the problem. I am trying to figure out correlations as to when and where the bluetooth starts messing up. For example I notice that it start cutting out sound quicker when using Spotify instead of the native Music app. Of when I'm closer to my microwave for some reason.
But....you have to be 'lucky' to get a senior engineer on the phone that takes you serious, is willing to listen, and is willing to run these logs. But perhaps we should all start to demand this. Write down when the bluetooth messed up in a few occasions, call them and then send them the exact times. Perhaps this will give them a better chance of finding out what's going on here. It's driving me NUTS.
Kind regards and good luck to you all from Holland.