The reason why the prices are falling is because of the upcoming ETH merge and you won’t be able to mine ETH anymore. The Polaris held its value because it was a good value mining GPU, in terms of games there are other GPUs out there. So it’s value is mostly there as long as ETH is mineable which might disappear this June.

Most likely when the exact date and block is confirmed for the merger you will see that many sellers are increasing their supply and decreasing their prices because these GPUs won’t have much use. Unless you got like free power at work and will be happy making a nickel or dime a day per GPU mining etc.