I'd guess that the hate on Twilight compared to those other stories is a function of popularity. Twilight was huge and overexposed; it culminated in a series of big-budget movies. Buffy wasn't nearly that big -- it wasn't on a major network and was overshadowed by some of the last real monoculture shows (e.g., Seinfeld and Friends). The Archie remake is even lower profile.
I'd guess that the hate on Twilight compared to those other stories is a function of popularity. Twilight was huge and overexposed; it culminated in a series of big-budget movies. Buffy wasn't nearly that big -- it wasn't on a major network and was overshadowed by some of the last real monoculture shows (e.g., Seinfeld and Friends). The Archie remake is even lower profile.