I kicked one off, if you’re interested! – https://www.indieforums.net/threads/c1c36e81a755848c.html
It has an unfortunately steep learning curve, but I like it because it is libre software that has been around for almost 50 years, and a huge ecosystem and community has grown around it.
One way to dig in to it could be to see if that same URL, when pasted in to the ‘URL’ section when creating a post manually in WordPress (not via Micropub), gets the correct values picked up. That could point whether it is specifically a parsing issue or a Micropub issue.
But I hope that just regularly posting and being visible as part of the wider IndieWeb is a useful contribution, too.
(My blog is WordPress but is not SemPress, it’s my own theme – https://gitlab.com/ngm/doublescores)