It may be a "boring" problem, but people aren't just paying for a reservation for nothing, ultimately they are expecting a car. And if there's no indication that they can meet the promises, that's a problem and he shouldn't be promising or giving wild production estimates in the first place.
Unless you believe that Musk is selling the ability for people to say they have a reservation. In which case there's no point to even bother building the cars in the first place.
but thousands of model3's are being produced and delivered every week. at this point it's just a matter of time for reservations to be filled and velocity will ramp up naturally as they improve their process. the investors panicking because velocity isn't doubled yesterday doesn't seem like long term thinking.
Unless you believe that Musk is selling the ability for people to say they have a reservation. In which case there's no point to even bother building the cars in the first place.