Guys, have just found that you don't need to enable a WiFi hotspot on your phone if you have a Bluetooth connection that you can also setup tethering on. On my Samsung Galaxy S8, there is a setting called Bluetooth Tethering, which has to be set ON to allow Bluetooth connected devices to use the Bluetooth connection for internet access. When I switch this on and disable my phone's WiFi hotspot, the Lexus uses the Bluetooth to fetch Streetview, fuel prices, traffic info, etc....
I've been vocally complaining that the car has to have two connections Bluetooth and WiFi, and it doesn't. I just needed to enable Bluetooth Tethering on my phone. I imagine most other high end phones will have this setting too, not sure what iPhones do....