It's fake IMAX. It's the type of IMAX that your local crappy Regal theater would promote. If you look at the size of a real IMAX screen and compare to a fake one, there's a huge difference.
BILLY: Hi Joe. Do you wanna go see the new Marvel in IMAX?
JOE: Is it at that Regal?
BILLY: Yeah.
JOE: Nah. That's not IMAX, it's LiMAX