The page could be more detailed + concrete than the blog post. It is also meant to be a starting point that can be extended by others.
There already is a page about directionality flipping, and it has a bit of "tips" section, but it's fairly small and it could (and should!) be expanded:
As @Mooeypoo said (thanks again!), there is already a page on mediawiki.org. I it does not make sense that we created another one.
What does make sense, though, is expanding the existing page (e.g. with some more general stuff from https://www.mediawiki.org/wiki/Extension:RevisionSlider/Developing_a_RTL-accessible_feature_in_MediaWiki_-_what_we%27ve_learned_while_creating_the_RevisionSlider). I will be trying to do it whenever I happen to have some spare time.