^^ I was thinking that they have the rights to remake the movie not the series BTVS, and BTVS the series focuses a lot on a brooding romance with a vampire. It seems to me if you start going down that route Whedon might have a case that they're infringing on the series.
You can't copyright a general type of storyline. What their lack of rights means is that they can't use specific
characters and events created for the TV series. They can use Buffy, Pike, Merrick, or any of the characters from the original film, but they can't use Willow, Xander, Giles, Angel, Spike, Faith, Riley, or any of the characters from the series. They can't use Sunnydale, the Hellmouth, the Bronze, the Initiative, or other locations or institutions specific to the series.
Now, if they tried to tell a story where Buffy got involved with a reformed vampire named, ohh, Gabriel who lost his soul and became evil when they slept together, then yes, that would be infringement, because it would be the same recognizable story. But human-vampire romance in general is not specific enough to copyright. If it were, then Whedon would've already sued Stephenie Meyer and won -- or, heck, Anne Rice would've sued Whedon and won.
No, but it's just silly. Buffy is already a very popular series and hasn't been off the air very long. Why not try to cash in on that by finding a way to continue the story instead of rebooting it?
Because the people doing this are the Kuzuis, who had no involvement with the series beyond getting paid for the rights to the concept. They'd probably rather develop the property on their own than go back to deferring to Joss Whedon. I don't think Whedon and the Kuzuis really see eye-to-eye. After all, Fran Rubel Kuzui directed the '92 film, and we all know that film went in a radically different direction from what Whedon wanted.