This is a brilliant idea and is broadly what underpins the mission of the IndieWeb space for the past decade. The difference is that it isn’t platform specific and a large portion of it is already built and working! Of course it’s in different stages and forms of usability for various platforms, but most of the building blocks already exist for a broad variety of platforms, including (and especially for) WordPress.
Because of the base level design, I can post on my site and syndicate content almost anywhere while often times getting replies and responses back from a number of platforms. Because it’s all built on open specs it means that people on WordPress can communicate directly with those on Drupal, Craft, Hugo, Kirby, Django, a variety of static site generators, Twitter, Mastodon, and almost any platform that chooses to support the broad standards. (Matt Mullenweg has already started down the road to having Tumblr support these building blocks.)
WordPress already has support for all of the major building blocks and works with a variety of social readers which make reading content and replying to it pretty simple and straightforward. Of course this doesn’t mean that there still isn’t work left to perfect it, smooth the corners, and lower the technical bars, and the costs for a wider diversity of people. For those that don’t want to deal with the hassle and maintenance, there are also several services that support most of the specs out of the box. Micro.blog in particular has a great user interface and does all the heavy lifting for $5/month. Without any cost, you can create an account and join that community using your own WordPress site today.
If you’re into the idea, stop by the IndieWeb chat, ask questions, and join the party. I’ve got a collection of posts with a variety of resources, descriptions, how-tos, and videos if you need them: https://boffosocko.com/research/indieweb/
Here’s a short preview of what some of it looks like in practice:

Aside: David Shanske, perhaps we ought to run one of our WordPress IndieWeb install fests one one of these coming weekends to help onboard people?