@mmasnick my current theory is that someone was told to limit any use of the API (in the [x]/api namespace) so they did something truly clownish like throw a regex match on all incoming api requests to return a 429, which is a legit rate limit status code.
if you look at all those requests when loading /home, you'll see that /home fails because it uses /i/api/[x] while /notifications loads because it is a first-class endpoint of its own.
i really think this is as ridiculous as a regex.