Instead, Fox have simply dropped the existing Pivot HD version of the series on Netflix. Although a small number of problems have been fixed (mostly in the first season) all of the other issues remain extant.
There is a current trend for 1990s and early 2000s TV shows to be updated to modern HD standards and turned from their original square-framed 4:3 aspect ratio into 16:9 widescreen presentations. The X-Files has had this done quite well and The Wire has had it done brilliantly (despite some creator concerns over what it might do to the effect of the show). Both shows were filmed and protected for widescreen, so it was possible to do this. The gold standard for such presentations is Star Trek: The Next Generation, the very first episode of which (now twenty-nine years old) literally looks like it was filmed yesterday. The only issue was that due to a large number of goofs around the edges of the screen (actors waiting for cues, light stands, crewmembers in show), the show had to remain in 4:3 ratio, as it was simply never filmed with widescreen in mind.
Buffy the Vampire Slayer had the same limitation when it was originally shot from 1996 to 2003. Joss Whedon did not film the show with widescreen in mind, and in many shots extras, equipment and crewmembers can be seen lurking at the edges of the frame. For the HD remaster Fox have occasionally used CG to paint out such issues, but far more often they've simply left them in or - unforgivably - cropped the shot by zooming in slightly to remove such elements fom the screen. Insanely, this has also occasionally resulted in actors losing the tops of their heads from the screen. Even more inexplicably, there are many cases where cropping has taken place for no apparent reason: several shots rendered in widescreen in full in the various title sequences are cropped when they appear in-situ in the episodes themselves.
Whilst profoundly annoying, this is perhaps understandable given the pathological belief that audiences need to have everything now in widescreen. What is not even remotely acceptable is that the show has not been edited back together in accordance with the original presentation. The biggest problem is colour grading, which has led to scenes filmed during the day but filtered to make it look like night now taking place during the day (even if vampires are in the scene), warm summer beach scenes looking like the chilly autumn days they were filmed on and characters vanishing into shadows or invisible characters suddenly being discernible in the background of scenes. There is also rampant DNR (Digital Noise Reduction) which, if not handled properly makes skin look unnaturally smooth, and a mish-mash approach to special effects, with some totally new CG effects included, and some old effects upscaled, to varying degrees of effectiveness.
What makes this more annoying is that some scenes show the potential of a HD Buffy, as the film has clearly survived well and some individual scenes look absolutely brilliant. A remaster was in fact desperately required for Seasons 1 and 2, which were shot on a lower grade of film stock to the rest of the series and look quite hazy, especially on modern televisions. As it stands, however, the HD Buffy remaster is an utter fiasco which borders on the unwatchable.
The reason for the mess is of course cost. Remastering Star Trek: The Next Generation cost $20 million. The cost of The Wire and The X-Files, although logistically not as complex (both shows being a lot newer and having far less effects-driven footage) was apparently not far off from that ballpark. Fox clearly did not want to spend that kind of money on a Buffy remaster and have done it slapdash and on the cheap, with no respect for the source material, the original artistic intention or the fans.
Buffy HD is a Facebook group which has been cataloguing the problems with the HD remaster of the series for some time now, and is worth a read for a full list of all the problems.