I do syndicate copies of some of my articles and notes back to the old .com site, in part as a back up as well as for a small number of people who only follow me there. There is a recent glitch since the update to 5.6 that’s causing some of my other posts to syndicate across as well, but they’re all done as private posts (I think). I should have that issue sorted sometime this week.
I’ll also note that the microformats mark up in your comments section is a tad off, so that you replies from your comment section are sending webmentions, but when parsed, I’m getting the original post back instead of your comment. I’ve duplicated it on my site, so you can see the “odd one” that came through as well as the duplicate which is what most would expect.
In my opinion it’s these small and unexpected microformats glitches in the WordPress (Theme) space that are preventing a more massive uptake of the plugins. But once it’s working, being able to do a cross site conversation from post-to-post and comment-section-to comment section is rather nice and elegant!