[restuijs]

Your own comment to me illustrates why some sort of space is better. In fact, I can't tell if you're being ironic or not.

Your post is difficult to read because the em dash looks the same as the hyphen later in the post.

The argument that clinches it for me is editing. If you use an em dash with most word processing programs, you will consistently run into problems with the dash and surrounding text being treated as single words. You could reprogram things to recognize em dashes in those scenarios, but the standard behavior exists because of the way the vast majority of people perceive text.

Personally, I think the solution is a thin space, or to drop em dashes in favor of en dashes or something.

I use em dashes frequently, and these issues are frustrating to me. It's also frustrating translating them to plain text.