This isn’t just end of the line vehicles, this is something that happens every year with the pickup trucks and other cars like the Malibu’s and Impala’s. When they first come out for that year, you pay MSRP or maybe a small amount off. By the end of the year they have so much overstock that they have to give you a lot of incentives to buy one, meaning it makes anyone who paid MSRP or close to it to take a huge hit when looking into resale without adding mileage.
Look at the price of any Silverado that is 2019 with 2020 models coming out. Same would have been with 2018 when the 2019 came out. They give almost $15k or more off.