WiFi is a better protocol than Bluetooth if you want to take music off your phone. Bluetooth will compress the stream down to MP3 levels. For me, I will only use a USB stick for my music. Getting a few 32G thumb drives together for that. The car needs FAT32 which is a surprise, as many will do NTFS these days. Still even if it did NTFS it would be difficult with all the data a big ass drive can haul. So categorizing my music and using 32G FAT32 drives for it is perfect.
So you are saying if I connect via wi-fi to my phone I can play music from there? And what about my home wi-fi, any reason to connect to that? Of course will only work when I am in my garage. But can I download music from my home computer or from the internet?
Your Solterra will most likely use its connection to your home WiFi for OTA updates (our 2021 Outback does). Also, when you connect your phone to your car's WiFi hotspot, it will in some locations give you internet service where you might not otherwise have it - IF your car uses a different cellular carrier than your cellphone. At least that's true in the US, I'm not sure how the various cellular companies' coverage maps differ/overlap in Canada.
This has been especially useful for us in the Outback. The car uses AT&T, our cellphones were on Verizon which has some notable network holes in places we travel to, so it was useful to have a backup data/voice connection at those times. We recently switched to Google Fi, which in the US uses T-Mobile and US Cellular, and even though its coverage seems to be better than Verizon's in some areas, it is importantly different from AT&T's - so we'll still benefit from having overlapping cellular coverage. So long as we keep paying the $25/month for the car's cellphone service.
I’m confused as to why I can’t connect to wifi and still use CarPlay. Or that I can’t just connect my phone to my Solterra via Bluetooth for music while connected to a different WiFi. I’m in a rural setting with poor service and the fact that they are mutually exclusive has definitely hampered my ability to sit in my car, listen to music, and use the internet. I can’t even connect to my Solterra hotspot without CarPlay shutting down, or have CarPlay connect my phone and rig without disconnecting WiFi. This make the digital key almost worthless at home because I don’t have good reception there and apparently the app needs an internet connection in order to communicate to the vehicle that the digital key is on the wireless charging dock… definitely a huge oversight that could leave someone stranded if they go camping expecting to use the digital key (or they lose their keys) without cell service.
I might be wrong but I think CarPlay uses the wifi network to connect to the car. So that would be why you cannot have both CarPlay and wifi. As for CarPlay and Bluetooth, that would be redundant for the phone and not necessary. I would think you could use Bluetooth and the cars wifi if you erase your CarPlay connection. But I don’t have the car to try it out myself.