Google and apple maps through Mazda Bluetooth

I have a 2015 mazda3 and have recently switched to iPhone.

previously when I used maps on my phone over Bluetooth (every android since getting the car) I could listen to the radio and the navigation from the phone would dim the radio through the drivers dash speaker and play navigation smoothly over the top. I would still hear the song and the nav simultaneously.

since getting the iPhone (12 pro max) the only way I can get navigation while

listening to the radio is by using the setting ‘play as Bluetooth phone call’ which is horrible. I get a loud beep then a few seconds of silence then I get the second half of the navigation instruction followed by another awful loud beep then silence before the radio kicks back in.

Can anyone explain what the deal is and why it won’t “just work”?

I initially thought it was a Bluetooth protocol issue but as far as I can see both the android phones and the iPhone use the same ones.

I don’t have CarPlay currently. I was going to get it installed but from what I’ve seen on the webs this is also an issue there. So not inclined to pay $500 to get it installed if it won’t fix the issue.

Anyone else having this issue?

halp!!