Edit* To be clear it seems to be browser independent. I use firefox on my mac and safari on my iphone and it seems every time I click a link to twitter I get an error and have to refresh the page.
So lots of people experience it, it's a long thread of examples. I can never load a twitter link on the first try no matter the device. This one took 5-6 refreshes to show up. Wonder why it hasn't been fixed for over a year. Surely they know about the problem?
Note that numerous of the Nitter instances are themselves rate-limted or blocked by Twitter, though I've found several that work reliably.
Disabling JS on Twitter helps ensure I remember to use Nitter ;-)
Essentially if I control a certain number of Twitter accounts and I have the handles of some of my own website users, I can selectively block those each of those users from different twitter accounts. In the background of my web site I can attempt to load tweets from all of my accounts and time how long these requests take.
Because blocked accounts load much faster than actual tweet threads I can statistically identify the users of my website by the combination of fast-loading tweets. The errors you get loading tweets not directly referred from Twitter is a consequence of Twitter attempting to circumvent this.
I don't know if it's a Twitter bug with requests that have the Referer set, or a deliberate thing with HN as the Referer.
Refreshing the page works to load the content.