This doesn't realllllyyyy answer your main question, but you got me curious how WriteFreely blog posts look from other platforms, and which ones can see them. So, I tried a few with this post of mine. Obviously some of these wouldn't make any sense, and also for some of them I may have just never figured out how to properly format the URL/search the way it wanted. But, here's what I got on every platform where I have an account:

• Mastodon: If you're logged in, it shows the title, any pictures, and a link to the full text. If you're logged out, it shows you a redirect option to the originating blog.
• Friendica: Shows the whole post roughly as it should look, albeit with a "read more" accordion.
• WAFRN: Shows the whole post roughly as it should look, albeit with all the pictures at the bottom.
• BookWyrm: Logged in, it can see the blog but can't retrieve the post. Logged out, it automatically redirects to the blog.
• NeoDB: Logged in, it can see the blog but not the post. Logged out, it asks you to log in.
• Lemmy: Can't seem to access the post or blog at all.
• PieFed: Can't seem to access the post or blog at all.
• Pixelfed: Can't seem to access the post or blog at all.
• Mobilizon: Can't seem to access the post or blog at all.
• Ibis: Can't seem to access the post or blog at all.
• Peertube: Can't seem to access the post or blog at all.