iPhone XR Apple Car Play takes over all vehicle audio

This question has been asked multiple times, and in the old thread I went to today, there were 711 "me too" responses. For context, this was an ongoing problem for me with this phone in a MINI Clubman. I connected the phone for the first time to a BMW X2 two days ago, and the problem developed last night and again today. This is a genuine nuisance, and I can't think of how this is acceptable. For reference I did ALL of the listed steps in the first post, and the steps in the Apple support message. Any suggestions from someone who has put this behind them, or do I just have to shut down my phone every day?

Original post (including their advice from Apple)

I have a problem that is driving me crazy. CarPlay keeps changing my audio source back to the Music app or whatever was last playing through the iPhone (iPhone XR , 128 GB). This has been an ongoing issue the entire time I've had a car that was CarPlay capable. When I listen to the radio or Sirius XM, it will change the audio source to the iPhone. When I switch back to the radio, it does it again. The only way I can listen to the radio is by disabling CarPlay. Something is making the phone think I want to listen to it and not the car's onboard entertainment sources. I have tried unpairing the phone and reconnecting it, countless times. I have tried restarting the head units in both cars. I have tried hard closing all the apps. I have tried restarting the iPhone but the problem persists. There was a similar question, actually the exact same question and issue published on May 16, 2020 and this was Apple's response: (All these steps have been tried as well with no luck)

1.    Check your connection to your CarPlay stereo:

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·       If you have a wired connection, try connecting again with a different USB cable to a different USB port if you have one.

·       If you have a wireless connection, make sure that Wi-Fi and Bluetooth are enabled under Settings > Wi-Fi and Settings > Bluetooth.

1.    If CarPlay doesn't activate automatically, look for the CarPlay logo on your car's display.

2.    Restart your iPhone and your car. 

3.    Make sure that Siri is on.

4.    If your iPhone isn't detected by CarPlay, make sure that CarPlay isn't restricted. Go to Settings > Screen Time > Content & Privacy Restrictions, tap Allowed Apps and make sure that CarPlay is enabled.

5.    Go to Settings > General > CarPlay, tap your car, then tap Forget This Car. Then set up CarPlay again.

6.    Make sure that your CarPlay stereo is using the latest firmware from the car manufacturer. Check your car's manual for more information.

Apple's second response:

It sounds like CarPlay is switching to your iPhone as the audio source instead of using the CarPlay entertainment system. We'd like to help you out with this further. 

If you've tried all of the steps you mentioned above, including making sure your stereo is running the latest firmware from the manufacturer, we recommend trying these steps next: 

1.    Forget the stereo from Settings > General > CarPlay > [stereo name].

2.    Forget the iPhone from the settings (stereo user guide for instructions).

3.    Rename the iPhone in Settings > General > About > Name.

4.    Reset network settings on the iPhone in Settings > General > Reset. This also resets Wi-Fi networks and passwords, cellular settings, and VPN and APN settings that you’ve used before.

Connect your iPhone to your stereo again and test it out. If the same thing happens the next best step would be to factory reset the vehicle stereo and test again. You may need to contact the car manufacturer for steps on how to do that. If further help is needed afterwards reach out to Apple Support: Get Support

I'm going to go ahead and reach out to support, but all advice appreciated. This is a new-to-me vehicle, and having the audio system hijacked by my phone defeats the functionality of both the system and the phone.