That looks like a variation on a Bloom filter to me.
https://en.wikipedia.org/wiki/Bloom_filter
In the 80's or so when I thought I was being really clever I came up with another variation on this and I recall being quite annoyed when someone on HN pointed out (many years later) that this was a staple of computing science for longer than that I had been busy with computers. So much for having original thoughts...
It does go to show that a huge number of inventions we consider foundational are really just from a normal person being in the right place at the right time. When a field is emerging there is a lot of low hanging fruit you can get your name stamped upon.
Author here, indeed a variation of bloom filters: https://x.com/lemire/status/1971279371131646063
Ok. I have blocked X at the router level here since Elon went certifiable so I can't read that link but I will happily take your word for it.
It's funny how this comment chain is about how names stick to ideas in somewhat arbitrary ways, and you are using "Elon" to explain a personal policy for information grooming.
I think 'don't give your data to assholes' is a pretty good policy, regardless of whether it is personal or business.