I don't care about CG trailers anymore, show gameplay or it's meaningless.
Teasers before there is much to show of the actual game. This is getting the name of the game out and the general idea behind it.
Exactly. It just sets a tone for what universe and fiction will be. Seems interesting and I'm personally mildly excited just because of how much I liked the Witcher games. In many other cases I would just wait for actual gameplay before getting excited.