I think it's interesting how we went from 4:3 to 16:9, and are now back to something very close to 4:3 again. And both changes were sold as "you can now see even more of the movie".
The cinematographer would have composed shots for the main 1.43:1 aspect ratio first while taking into consideration the other aspect ratios (the viewfinder will overlay the different framelines to help make those decisions). The DP then gets to go back in during post and recompose each shot for the different formats as needed, tweaking what was originally shot to do their best to maintain a cohesive feel and emphasis across each crop. With five different formats for The Odyssey[0], I'm sure that was a fun experience.
It's not that one format is inherently better. The frame is a storytelling tool, and you can use different aspect ratios to influence how audiences perceive the film.[1] It's when you start changing it afterwards with little regard for the director's original intentions that we see problems. The old pan-and-scan movie releases for VHS or cheap 16:9 conversions are frustrating examples.
0. https://www.odysseymovie.co.uk/explore-formats/
1. https://www.cined.com/aspect-ratio-as-a-storytelling-tool-a-...
In 4:3 the framing is quite tight, and actors mostly fill the vertical space and the width feels somewhat constrained.
Widescreen movies are framed about the same height as 4:3, but with more space on the sides.
IMAX is filmed with the same width as widescreen movies, but with more space added to the top and bottom.
You can typically crop IMAX to widescreen without cutting off actors heads, but you cannot really do that with old 4:3 aspect shows or movies.
And that is typically what happened. Typical 16:9 flatscreen TVs at home offer a larger angular image size than the typical 4:3 CRTs did. And typical 1.43 IMAX viewings offer a larger angular image size than typical 16:9 flatscreen TVs.
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.