OK, so the only bluetooth I have is the one in my car and all I have is a little dumb phone (flip phone).
How vulnerable does that make me and what are the ramifications if any?
Even that "dumb" (I.e. not a smartphone) little flip phone probably has Bluetooth capability and is vulnerable and is most likely never going to be upgraded to not be vulnerable. It's also unlikely for you to be able to turn its Bluetooth off. It could become infected but not affected, as it's not a smartphone, but perhaps it could possibly become a carrier, and perhaps infect your car or other Bluetooth devices you may encounter. This is all highly speculative and highly unlikely to happen, just possible.