An adapter could simulate the pilot signal, but the Supercharger is configurable on the fly to control what power it draws when there's no signal, which is safer than faking a signal that might not match the circuit.
Does it "remember" the last setting, or do you have to set it each time?
My thought is, because the adapter is not telling it that 40A is available, it must remember that setting... otherwise you would have to set it each time you plugged in at home until you get an EVSE.
DigiNow needs to comment on that, or I can when I have time to dig around to figure out what the final decision was (tonight or tomorrow); I have to update my software to the final version, for example.
What I've been working with has defaults that have to be overridden each time. However, it's become easier to do that as the control software has matured, and I imagine or might encourage some of those overrides to be remembered user preferences, so you can hit a big button for "yes, this seems to be a real deal 50A/220V drop" or "6.6kW".
The control system is capable of remembering quite a bit across sessions in principle, but the risk of assuming a certain power level moving from one signal-less connection to another is overloading a newly-introduced charging circuit.