It went much farther - CinemaScope 2.35 to 2.75, or even Polyvision 4.0.

To me, the big wide screen Hollywood titles are 2.35:1.

To me IMAX 70 is cropped on the left and right compared to CinemaScope. Watching an IMAX 70 film in a normal theatre at wide screen aspect ratio crops the film again, so it’s effectively cropped on all four sides.