I noticed the website has some kind of delay, because the API returns the response in one fast block, while the site seems to type it out slowly. My theory is

I noticed the website has some kind of delay, because the API returns the response in one fast block, while the site seems to type it out slowly. My theory is it just inserts some sort of delay() based on the server load so you can't overload it. So everyone gets it slowly, setting consistent expectations. It seems more naive than malicious. It's like how TCP distributed the load across individual connections. Then somebody invented download accelerators, which split up a file into a dozen connections.