Reading through yesterday's post, I thought, "I can do better than that". I remembered that I had Matthias Pfefferle's Activity Pub plugin for WordPress, but had not previously activated it. But I did so, and it works. It transforms WordPress posts directly into federated posts, with a variety of formatting options. Since I will be using Activity Pub only in order to announce blog posts, it is sufficient to include just the excerpt, the link, and maybe tags.
This is the simplest federation option for my needs, so I will deactivate the Mastodon and Hubzilla plugins, and anyone who wants to follow me can use email@example.com, or http://vikshepa.com/author/hosh
, whichever works. I'm a blogger; not a social networking person. I only need to provide the options to make my stuff available (but without pushing it under anyone's nose). That's all I care about.