what about lost interest? 7 years' worth
They gave their money for a Cybertruck, and the liquidity from those reservations was most likely use to posture company assets/P&L, earn interest in a treasury, and whatever other financial weasel techniques that the lawyers and financiers of the world's first trillionaire - Elon - have in mind to use.
Customers didn't get that, and instead had a hold on their money for reasons and means BEYOND receiving the particular commodity that they offered their money for. Forget the pro-regulation and antitrust crowds being discussed in this comment section, you'd be hard-pressed to find even a Laissez-Faire economically-right individual that sleeps well to that notion.