I’m getting sick of artistic high horse rants from self-important idiots who think that Typographers are the individuals who should dictate how people type. This is not the only instance of it I’ve seen lately, but it’s getting worse.
The monospaced font typing conventions are all correct, all of the time. Any failure to render this into a form that pleases the typographers should be brought up with the software authors.
Why? Computers can fix this shit up trivially. There have been computer typesetting systems around for longer than there have been WYSIWYG wordprocessors (such as TeX) and they have never had any problems with correcting the spacing between words or around full-stops. You also need a way to differentiate between abbreviation stops and sentence stops, and the two-space/one-space convention is an excellent way to do this without needing to maintain a dictionary of all abbreviations.
On top of all of this, some of us still work in mixed monospaced and proportional text environments all of the time, and will copy content between them constantly. Computers are supposed to make our lives easier – part of that is maintained through consistency. Declaring that the method in one context is incorrect in the other is utter rubbish in usability terms.
There’s also absolutely nothing that says that spacing in a document should actually be honoured to the level that it is inside rubbish like Microsoft Word – if whitespace was automatically collapsed and reflowed, it might force people to actually learn to use the tools correctly.