Used prices have plummeted in part because new prices have dropped a lot. If new prices stabilize (big if), the resale value should retain itself a bit better going forward.
It's normal for a 1-year-old car to lose 20% of its value compared to a brand new model. But if you bought a $60,000 model a year ago, and that model dropped to $50,000 new, then your one-year-old car might only be worth $40,000 or so (20% less than a new car, but 33% less than what you paid for it).