I think, some confusion, at least mine, comes from comparing bicycles to motor bikes. I imagine you are right that initiating a lean with a bicycle without steering should be fairly doable. The confusion, is motobikes are much heavier, and with heavier wheels, maintain much stronger gyroscopic forces. So while I recognize the ease of your experience leaning a bicycle. It becomes much more difficult with a motorbike.

Bringing this back to the original post. Looking at this thing, I imagine it'd be hard to properly lean it given what appears to be significant heft.

Edit: To be clear, I mostly agree that it's the lean that's the primary factor in the turn. Just a subtle bit of confusion over how important steering is over initiating the lean in heavier bikes.