I have thoughts re:
"""
From your perspective, those replies disappear, and new ones won’t appear at all. Your instance silently enforces these boundaries by ignoring unwanted interactions, even if the sender’s server is unaware and still allows them to post.
"""
about the concepts of who "owns" (and can curate) the comments section of their post, from whose perspective. (It's never going to be a single person curating/moderating, but I.. think?.. people feel ownership feelings over it nevertheless.)