Im not sure what this will do. If they shut down Nostalrius, we will just move from one private server to the next. They can't close every private server in every country. They just attacked Nost since they knew they could(it's situated in French). Also the server owners were Blizz fanboys. A TBC server that has had 25-ish players for a year recently got a surge of thousand+, and another Vanilla server is so full it's starting another server.
Also pristine realms are a concept I have been thinking about as well, while they would be great, im not sure they would satisfy the urge. Nostalgia is a powerful thing, and cata+ zones(and dungeons) are boring. Also, the populations would be dispersed across all the expansions lol. But hey, setting a few of them for their non-nostalgic players probably wouldn't be bad.
Edit: Also, with their reluctancy to set up serers, they essentially want people to buy their expansions instead of playing Vanilla and never caring about any expansion sets ever.