No, these rigid format requirements are not designed to make the writer suffer under an oppressive editor's insane rule. Believe it or not, every one of these format requirements exists for a legitimate, sensible reason. Let's look at them one by one. It is easy to read, and most importantly, easy to use to calculate your story's word-count accurately. Word-count is important with short stories, since most short stories are bought by the word.
Editors live by their eyes.
If you make it too small, they will have trouble reading it. You want to make reading your work as painless as possible. You must leave them enough room to write clearly and legibly. And believe it or not, people have made the mistake of adding an extra space between every word, rather than between lines. Again, you must leave the editor room to work.