While I do agree that the film is revolutionary, I don't think its a gauge of how far we've come. Heck, when you look back at the original Night of the Living Dead, with its black protagonist, that was a major step forward, but can we say that society stepped as majorly as that film did?
For me, it depends on what different groups of people are seeing when they see the film. Are they seeing themselves? Are they inspired to go out and learn the history and the persisting issues that the film addresses? Or do they see the film as a release valve for their own anxieties and frustrations, some about Trump, and the movie as a symbol of the amorphous "Resistance" that is about style as much as substance? Do they focus on the comedy of Rod's character and not exactly what he was saying? Or do they see it merely as a good movie or funny movie and that's it? The horror-comedy format made the film accessible but at the same time it also might be not taken as seriously as say The Birth of a Nation or Malcolm X. And I can't help but look at Get Out's success in light of how Nate Parker's film has all but been erased from the memory of Hollywood. Rotten Tomatoes wouldn't even put a certified fresh sticker on the man's DVDs/Blu-Rays. I chalk up Get Out's success to it being a good movie, but also to whites' comfort with Jordan Peele. They likely weren't expecting a film like that from him. I know I wasn't. And can whites merely write off the white characters in the films as aberrations, which is something whites have shown a great ability to do for a long time. That various white malefactors are not symptomatic of their entire race or their cultures (i.e. all those white serial killers and mass shooters) unlike black criminals who are often portrayed as representing cultural/racial traits endemic to black people.
I see it as Get Out communicating two things to blacks and whites and arguably other people of color who would be attuned to feeling like an outsider. Though it should be noted that Peele did include a person of color amid those who were bidding on Chris. Now, I don't see it as revolutionary to acknowledge that blacks have been treated bad in the past and that are being treated bad now. It can be revelatory for some but not revolutionary if you see it and then just go about your business and not figure out how can you be a part of changing it.
So in "short", I'm not jumping the gun on this film's power to effect social change. Hopefully it can get some self-reflection and conversations going though.