I'm thinking in my head right now of the 10 or so most famous horror movies and most of them don't even have a black character (Psycho, Halloween etc). Others do but the black guy is competent and lasts a fair amount of time (Alien). The Shining is the only one that even fits the rule you mention.
And even that one is only one by a technicality. When people say it, they mean a group of people (probably teens) of which the black guy dies first. Where as O'Halloran is only the "first" to die because he's the only one who dies. He's set up throughout the movie as a possible ace-in-the-hole to use his power and save the day and like two hours into the film, he finally arrives and... gets an axe to the chest. Hardly redshirt territory.
You're absolutely right; it IS revisionist nonsense.