When I'm simply typing in an etherpad on the Wikimedia install (mac, chrome), and while not being the most prolific typer at all, I get an error saying that I'm being rate limited. See attached. Other users were experiencing the same (but at higher speeds?).
I tested myself here: https://etherpad.wikimedia.org/p/B6GSr_Ip3YNBf0KFDl6G