Nobody did

Or you can have Alister McGrath (yes, really, again) recycling his jeers and fleers. He says about the (terrible) idea of rebranding atheists as “Brights”

Dawkins’s advocacy in the United Kingdom proved especially successful, persuading many in the media that a new force was emerging in western culture. “The future looks Bright,” they declared.

No they didn’t. McGrath is quoting a ”they” who never existed. No one in the UK media was persuaded, and “they” certainly never “declared” that the future looks Bright. I think one editor once used that as a title. Editors do silly things with titles; that means nothing.

He goes on to make the obvious point that there are lots more theists going to church than there are atheists going to “Brights” meetings – which is true, but then one reason not to be a theist is so that one won’t feel obliged to go to church every week. (“Oh but community!” comes the cry. Yes yes, but all the same, Sunday morning staring at the hummingbirds instead.)