Presumably that you are talking about the CloudLinux LVE, free hosting have that exact system asaik, except that when you hit a limit you get straight up suspended, not throttled.
Yes, which is why those examples you mentioned will also get you suspended.
Ultimately these are about two special limits on the free hosting: browser limit and hits limit.
Free hosting sends a JavaScript challenge before first load and verify the cookies afterwards, meaning a request could take more computing power than normal.
There’s also a hit limit. That’s what’s actually doing the jobs as banning accounts whose website makes excessive requests to the server, not the “chat” keyword as what you may have imagined. Other cases don’t have a keyword banned because it’s generally hard to find a common keyword unlike “chat”.