"All right, let's write this out with #LyX."
(Typing. Done.)
"A but I need this specific format for this one thing... how the hell..."
(Many hours later)
"OK, that hack seems to kind of work. Let's render it now to RTF. Crap, that doesn't work. Ah my MacTeX is from 2017, maybe that's why..."
(Now downloading new 5.51GB #MacTeX)
Let's see how this ends. Original text was in #IAWriter but that had even less layouting features and I wasn't in the mood to learn how to do a custom template.
Specifically: I need a top left address and right aligned word count (preferably top-aligned with the left address), before the title. Can't see any obvious way to do that with #IAWriter short of doing a custom template.
For the record, having left address and right address (or anything) side by side at the top of an #IAWriter document seems to be possible by downloading the letter template, though it is a bit hacky.
In that template the first and second environments get laid out side by side. So write your address, separated by newlines (3 spaces + return), then start a new paragraph, indented. The new paragraph will float at the right.
Except unfortunately this #IAWriter trick doesn't work for exporting to Word documents, where that layout doesn't appear to get applied. Oh well. I guess for now the quickest is just to manually do something inside Pages and export from that (I don't have Word). But it would be nice to have a proper workflow.