I realise that my comment up there will be downvoted into oblivion for expressing an emotion (and this one for remarking on the downvoting), but in all sincerity I don't understand why people do this.

A landing page is not a movie poster. It's meant to sell something. To sell something customers must know what that something is.

Even luxury goods companies -- the fondest of vague advertising -- have a picture of the product so you know if it's a handbag, a bottle of perfume, a watch etc.