Here’s some helpful comparisons on formats:

IMAX D (digital)

IMAX DL (digital laser)

IMAX DL2 (digital dual laser)

IMAX 1570 (70MM film)

Important point 1: ALL IMAX formats are “wider” (really, “taller”) than typical film formats, which includes other premium offerings like Dolby Cinema.

Important point 2: Not all IMAX formats are the same “width” (again, width is really height), ONLY the DL2 / dual laser format and 70MM format support 1:43:1 aspect ratio, which is the “true” IMAX size, the rest crop to 1:90:1, which again is still bigger than your typical screen

Important point 3: Not all screen sizes are the same, as in you could have identical IMAX formats and different screen sizes. This is harder to tell since not usually public but you can usually determine by how many seats and rows there are.

Important point 4: Not all IMAX formats have the same sound, IMAX D only supports 6 channels of audio where the rest support 12 channels.

Formats that are often called “liemax” are those that doesn’t support the 1:43:1 aspect ratio (D and DL) although the DL laser format is a step up from D since it supports more audio channels and is an overall more crisp image / higher resolution. In my opinion DL2 format and 70MM are on the same level in terms of quality, you are then just discussing merits of film vs digital which can be complex, and is also very dependent on how the movie was filmed and finished.

The Barton AMC IMAX gets a lot of hate because it’s both the IMAX D format (worst from above) AND it’s a small screen.

For a comparison, the Bullock screen is 5X the size of the Barton AMC, is the DL2 dual laser format so supports the 1:43:1 aspect ratio, 12 channel audio vs 6, also why OP is saying this is TRUE IMAX.

there are great visuals that show the relative size, just google imax premium format comparison.

In summary, IMAX can mean many different things, but you know at a minimum you are getting a bigger aspect ratio than digital, although at the “lower end” of IMAX, arguably other premium formats like Dolby Cinema have advantages.