Earlier quoted context omitted.
You missed what he said. He copied the actual data into chatgpt as part of the prompt, and it gave the correct information. without that data, it might, or might not, give correct info, and often it won't.
You can't feed anything more than a fairly short Wikipedia article into ChatGPT, its context window isn't remotely close to big enough to do that. It also doesn't change the point that copying data has no effect. You could just ask ChatGPT what years the Mets won and it will tell you the correct answer. To test this, I pasted the Wikipedia information but I changed the data, I just gave ChatGPT incorrect information…
Or it might make something up.
You don't ever know, and you can't know, because it doesn't know. It's not looking up the data in a source somewhere, it's making it up. If it happens to pick the right weights to make it up out of, you'll get correct data. Otherwise you won't. The fact that you try it and it works means nothing for somebody else trying it tomorrow.
Obviously putting the data in and asking it the data is kind of silly. But you can put data into it and then ask it to provide more nuanced interpretations of the data you've given it, and it can do reasonably well doing that. People are using it to debug code, I've personally used the ghidra plugins to good effect -- the way that works is to feed in the whole function and then have chatgpt tell you what it can deduce about it. It generally provides reasonably useful interpretations.