In the main part of your question, no, there’s a general global system volume. However specifically in maps there is a setting to control the volume of the directions relative to any playing audio. You may have to be in navigation to get those settings.
iPhone
I found a volume setting in Google maps (soft, normal, and loud) but I cannot find anything of the like in Apple Maps. Still looking though!
Could not find a volume setting in maps. I found one in Spotify and went the other way, turning down the music. It appears to be working much better now. Thank you.
Oh nice, it’s smart of Spotify to have that. There may be a loudness setting for Apple Music in settings if you’re ever listening to that.
Currently i have apple music uninstalled because i only have the theme to 2001 on it and my wife's car kept opening it instead of Spotify when it connected to Bluetooth. When iOS 17 releases i may revisit apple music.
No there isn’t. iOS doesn’t have the settings granularity that Android does. It can be frustrating at times, but the benefits largely outweigh the QOL shortcomings for me.