The bet a lot of people made was basically, since we can have a market of these random things, and they are actually non-replicable at the actual ERC721 assignment level (I know you can copy and paste the actual pictures), that those ownership assignments just become part of the greater pool of “currency”, with some having greater value than other.

They will probably retain some value indefinitely, in the same way Beanie Babies have managed to hold on to some value even today. It’s of course just not even close to the peak bubble value, because a lot of people were behaving irrationally purchasing them with the whole fear-of-missing-out attitude, driving the price up further, vicious cycle.