But that's assuming that the story is what makes the film great, which in horror films is rarely the case.
Suspiria has a terrible thrown together plot, but the plot isn't what makes the film so legendary among horror fans; the way it's shot, the eery lighting and the atmosphere of the film is. The kind of things that get changed for remakes.
I don't see why they should "bring the story" to a larger audience. Suspiria and Let the Right One In are supposed to be cult films. The idea is that they are meant for people who are already horror film fans. Films like that are made for their audience, the directors do not have to change their films to appeal to more audiences, if either film was made by a Hollywood director rather than low budget Italian and Swedish directors they wouldn't be the same films, they would have been torn apart for the masses. I'm not trying to be snobbish saying these films are better than Hollywood crap, because there are loads of Hollywood films I like, but the fact is a lot of the general public would not like these films, as they are not made for a big audience of the majority of the population, they are made for a smaller audience who already enjoy that type of film. Remaking the same films for a larger audience is just demeaning to the artistic integrity of Dario Argento and Tomas Alfredson.
It's the same thing as a lot of the art and/or entertainment industries nowadays. It's all about making money, rather than making good or original films.