This reminded me of work to get the C64 to do 80 columns in software, using a 3x7 pixel grid (with one row and column used for spacing), some of which were part of commercial products.

https://www.pagetable.com/?p=901

> Creating a 4×8 character set that is both readable and looks good is not easy. There has to be a one-pixel gap between characters, so characters can effectively only be 3 pixels wide. For characters like “M” and “N”, this is a challenge.

I remember using Tasword Two for the ZX Spectrum. Even with a 3x7 font (4x8 grid) it only achieves 64 characters per line. Apparently in Tasword III the authors implemented 128 characters per line - by scrolling.

Competitors could apparently show 80 characters per line, but only by switching to a horribly unreadable 2x7 font. "I found the tiny 80 column characters tiring to read but the mode is useful if you want to see what the finished output will be like." - https://www.crashonline.org.uk/31/words.htm . I can't find a screenshot.