What is nitter and why does it still work?
You can't access X without signing in, then there are the rate limits if you are signed in, but these things are not an issue with nitter. I went from checking Twitter as a logged out user every few days, to not using it at all after the access changes, to casually using nitter to check in on a few accounts I like.
I think it uses the same functionality as the guest account feature in the Android app as of now.
Historically it worked by using Twitter's undocumented internal API, but I have no idea what it does these days.
Its not even getting rate limited anymore.
No clue how it works nowadays
The author made a post bragging about how easy it was to circumvent rate limits since X doesn’t even limit by IP address, so they had 1 address making requests for like 1000 accounts without any problems.
When I checked this a few days ago, Nitter wasn’t returning the latest data, so aggressive caching would be one of the tricks they’re using.
I self-host a LAN-only Nitter instance for personal use. In the last few months of Elon trying to lock out third-party clients, it's gone from automatically acquiring tokens, to tweet access breaking and coming back and eventually breaking again, then only showing "top tweets" for users rather than full post history, to having to log into Twitter in a browser and extract some cookies/headers using Developer Tools (and failing to show user post history because they tried using RSS feeds that got pulled). The latest development is the use of "guest tokens" (https://github.com/zedeus/nitter/pull/985) that you have to create and install by hand (running a Node script) because Nitter hasn't automated the process yet. This works well for viewing all tweets, but hasn't been merged to the master branch yet (but nitter.net and the AUR nitter-git package are already using it).
Spoiler: because apparently, it's API access somehow hasn't been pulled yet.