I think it's the pacing that gets people. This movie has weird fucking pacing. I ended up vibing to its wavelength, but I can see how you wouldn't. It strikes me as the kind of movie that will be revered as a stone-cold classic in a few decades.
Starts and ends with a bang, and because it's a play it has a cool structure, but of course that makes it inherently uncinematic. And certain sections remind one of why Friedkin doesn't make movies anymore. Honestly I feel kinda depressed that I just watched Gina Gershon getting messed up like that. Wasn't on my bucket list.
It's inherently a fool's errand, making real human beings say the deliberately inhuman dialogue of Don DeLillo. Every actor fails because it's an impossible task, and it's about as insightful as Robocop (I don't like DeLillo's cynical philosophies, but I like reading his writing) so I can't explain why I found this so entertaining. It's one of those Brown Bunny/Twentynine Palms type of things, where I should be hating everything on screen (in fact that's kinda the point) and yet I'm inexplicably enthralled.