I have a Tesla 3. There’s no good way to get a lot of power out of the car as an end user except via the wheels. You can get like ~1kW of 12VDC via the dc-to-dc computer/accessory system but even that is pushing it.

I am saddened by this. I’d like to be able to access the large amount of power in it in a pinch.

There is also no good way to charge it as an end user from a DC source like my large 48VDC solar battery system. I end up having to invert the DC to 220VAC which then charges it normally (involving rectifying it back to DC for the onboard batteries) - an unnecessary and inefficient double conversion.