OG ayashii world was essentially a guest book (no threads, no trees,
just long twitter-esque post chain). I think Ayashii.net adds a lot of
nice, handy, human features to the basic concept and I enjoy the chat
here. What do you think are services that are essentially cousins of
Ayashii.net?
I found https://postzone.app/ today and think that's another creative
imagining of the "chain of comments without registration" concept,
easy enough to clone too. (there's a quasi-CSV file that logs comments,
the JS can post/read/delete entries from that in nearly real time).
The feature of being able to delete any comment you want is also pretty
sweet.
Something like forced-anonymous IRC software, like what's available
at irc.sageru.org (eg ircs://irc.sageru.org/jp ) seems to also come
close: type anything you want, and as time goes on, old messages drop
into the void.