If your goal is to have other people read and enjoy your writing you should make an effort to edit your thoughts.
[edit - putting comma back in to break up the long sentence] If your goal is to have other people read and enjoy your writing, you should make an effort to edit your thoughts.
I think this is the only aside formatted like this in the article. The other em-dashes take the place of pauses in sentences, places I would normally use a comma or semicolon, or are used to introduce a list where I would typically use a colon.
Personally I write with too many asides, normally done with commas and parentheses. It's a comforting habit to fall into, and makes getting your thoughts out so much easier, at the expense of interrupting the reader's train of thought.
I don't normally notice when I'm writing with asides so the jarring em-dashes were a good reminder to try and edit them out where I can.