I found the tool submission you're talking about, I remember putting my username into it when it was first shown and it did produce a list of accounts with % probabilities (in my case all unrelated to me), but when I tried doing it again now it says "This user does not have any public activity in the previous three years." for "swores" (and I've multiple comments just this week).

Luckily for the throwaway person above, it says the same for them. But does still show results for some, maybe only big accounts now?

https://news.ycombinator.com/item?id=27568709

edit: ahh, I think it just took a one-time snapshot of the three years leading up to its 2021 creation, as my old username that I changed to swores does show up. So it's an interesting proof of concept that someone could do similar analysis, but not an ongoing tool. So it won't be telling us which CTO to avoid :P