This second hand market issue is a real problem - customers can change their mind, or move, or extend their family and need to buy a car. In this case, you are basically stuck with your bike. This is a problem you don't have if you buy an ICE bike (you know exactly for how much you can sell it) or even a BMW Evo scooter (there is an active second hand market).
It is of course not possible for Zero to "make this market" - Zero is a very small company with limited resources. But they could definitively be nicer with customers when big costly issues happen after the commercial warranty period. EV have a bad reputation for battery longevity, and Zero had several quality problems especially with the first models. I also understand that the situation in the US is much better than in Europe (might be timezone or language issues, or Zero putting a lower priority on Europe ?).
Nobody cares with replacing a minor part, or paying a bit more than usual to replace plastic part, but if customers know they might have the pay their bike's value in repairs, they just wont buy a used bike. If people are not able to sell a used Zero, then many people wont buy a new one.