Because it's more convenient to buy a new fridge than to seek out an old one in good condition on the used market? And because they don't manufacture old fridges so the remaining good ones fetch a much higher price? And because there's no way for a consumer to reasonably determine the longevity of a new product before purchase?
I don't necessarily think that's why people aren't buying this fridge but those are reasons why new products can still be successful even when they're worse than the old ones.