twtxt isn't very popular.
I think the feed format itself is neat, other than the tab, but maybe there isn't enough of a niche for it.
I have implemented a twtxt version of the Atom and the JSON Feed feed [1] for my site at https://dbohdan.com/twtxt.txt.
The generator I originally developed for the site creates twtxt feeds, too: https://github.com/tclssg/tclssg.
I haven't seen it in another static site generator or plugin;
please link if you know one.
quite https://lublin.se/twtxt.txt 2024-12-23T03:15:21-05:00 <ROBOT VOICE> THE LAST HUMAN POST ON THIS FEED IS MORE THAN FOUR YEARS OLD. PERHAPS TWTXT CLIENTS SHOULD THEN FETCH THE FEED *VERY* RARELY.
quite https://lublin.se/twtxt.txt 2024-12-23T03:15:16-05:00 <ROBOT VOICE> THE LAST HUMAN POST ON THIS FEED IS MORE THAN FOUR YEARS OLD. PERHAPS TWTXT CLIENTS SHOULD THEN FETCH THE FEED *VERY* RARELY.
quite https://lublin.se/twtxt.txt 2024-12-23T03:15:07-05:00 <ROBOT VOICE> THE LAST HUMAN POST ON THIS FEED IS MORE THAN FOUR YEARS OLD. PERHAPS TWTXT CLIENTS SHOULD THEN FETCH THE FEED *VERY* RARELY.
[...]
[1] This is why you shouldn't include the word "feed" in the name of your standard for feeds.
The directory at https://git.mills.io/yarnsocial/we-are-twtxt gave me an error, but I found it in the Internet Archive (19th September 2024):
https://web.archive.org/web/20240919022045/https://git.mills...
Here's a live example from that list: https://niplav.site/twtxt.txt - and that one shows ones its following, this one has recent posts (from December 2024): https://txt.sour.is/user/xuu/twtxt.txt
The last commit to https://github.com/buckket/twtxt/commits/master/ is October 2023, so I don't think this project is 100% thriving at the moment.
Update: Aha! Found https://twtxt.readthedocs.io/en/latest/user/registry.html and via it https://registry.twtxt.org/api/plain/tweets which shows some recent content across the network.
Also https://registry.twtxt.org/api/plain/users looks to be a list of users, though I couldn't figure out how to paginate it (using ?page=3 doesn't seem to work, despite that being listed on the https://registry.twtxt.org/swagger-ui/ page)