As the author says, you can follow my blog from your Mastodon account, so you see my posts as Mastodon toots, and you can reply to them and leave a comment on my post. I don't know why there isn't a Wordpress plugin, I guess nobody wrote one yet.
And will all of your followers’ comments show up too?
Is this essentially just the same as the trackbacks I already get from other Wordpress posts that link to my page, but with every single tweet (or rather, “toot” (oh, pardon me, how rude. Can you please tell me where the bathroom is?)) generating a trackback?
If you don't want a specific person's comments? You'll need moderation or blocking tools.
If you don't want any comments from the fediverse in general? Well then activity pub doesn't benefit you at all and you have no need for it.
> Is this essentially just the same as the trackbacks I already get from other Wordpress posts that link to my page, but with every single tweet (or rather, “toot” (oh, pardon me, how rude. Can you please tell me where the bathroom is?)) generating a trackback?
You can interact with people's content from any interoperable website/service/client basically. It's not just a link on some site or a meaningless metric that gets bumped up. The comments may very well be from people who actually did read your blog post and genuinely want to interact. They just don't have to actually visit your site to do any of those things.
