You forget that 3rd parties have been returning 1080's to Nvidia by the hundreds of thousands. At least one has given back over 300,000. And that's just one. They will go down. Don't kid yourself. They aren't going to destroy them, they will lower the price and sell them.
Edit:
These articles are from this week.
https://www.tomshardware.com/news/why-gpu-pricing-will-drop-further,37444.html
https://www.pcgamer.com/there-might-be-a-big-drop-in-graphics-card-prices-next-month/
https://www.kitguru.net/components/graphic-cards/matthew-wilson/gpu-prices-reportedly-expected-to-dip-by-20-this-month/