@BobLefridge

Am aware of pan and scan (cropping, selectively) and letterboxing. Both of which are addressed in OP.

Pan and scan requires someone make editorial decisions about what is seen through the window and what is cropped out. Letterboxing was often not acceptable to audiences, as you note.

For Saturday afternoon movies, especially on UHF channels, horizontal compression was a way to avoid sacrificing screen real estate without actually doing any editorial work. Another reply to this thread provides the term "anamorphic widescreen".

The question went to the impact, on later art, of folk growing up with such squashing of film for broadcast. Not to alternatives to such squashing, as if the lived experience of seeing such squashed films on television never happened. A non-responsive answer is non-responsive.