I also hit errors following links to twitter more often than not, reliably, on all sorts of environments. It feels like they’re doing some kind of cache-related routing based on headers. Often “refresh” doesn’t fix it, but hitting enter in the address bar does. Seen on iOS, macOS, Windows, and Linux, mostly in very normal browsers (I’d expect mobile Safari in particular is at least on their top-5 most-seen browsers). I’d assumed they were trying to annoy me enough that I install their app. I’ve seen many others report the same kind of reliable, very frequent errors.

Notably, I’m also not logged in, which might be another thing they’re trying to get me to do and another difference between those who hit this more often than not, and those who rarely or never see it. It’s been like this for years.