Threads adds ‘ghost posts’ that disappear after 24 hours

Sarah Perez, writing for TechCrunch:

Users will now be able to create a ghost post on mobile devices by toggling on the new “ghost” icon on the app’s compose screen. When the post is published, it appears in others’ timelines with a dotted conversation bubble around it to differentiate the post from other content.

Other users on both desktop and mobile devices can reply to the post, but these responses are sent directly to the poster’s DMs (direct messages); these replies don’t appear in the timeline.

May be it’s because I’m old, but I’m failing to see the novelty of this feature.