As a few people have pointed out, 6.2.3 won't get subs back, it's a good patch in terms of rewards, but it has no content. It may somewhat stop the bleed, but it won't fix WoD's problems, it's too late for that.
But what it does seem to be doing, is improving Blizz image, a little.
Right now Blizz image when it comes to WoW is at its lowest. There's hardly anything positive said about WoD in the WoW community (which is made up almost entirely by that "vocal minority"). They can't add store mounts without backlash. Most interactions with devs are antagonistic.
This patch is Blizz's attempt at changing that. Better rewards, in-game rewards, stuff not actually going to the store, even though it was intended for the store. That's them trying to show they care, somewhat.
It seems to be working, to a certain extent. You can see it in some threads here, and some known WoW youtubers have already expressed how they like the patch.
Will it last? I don't know. It feels a little late, and in the grand-scheme of things, none of it is actual content.