We implemented a similar thing a few years ago at a company I worked at. We designed a very fast system zero-knowledge matching over zillion entries. It was way

We implemented a similar thing a few years ago at a company I worked at. We designed a very fast system zero-knowledge matching over zillion entries. It was way faster than the "competition" (which arguably were slow because they just never cared). It took a few hours instead of a few days to run, basically. While the results were 99.99% the same as from the slower solution, customers would think "it can't be right" or other things like that, and wouldn't trust the product. We'd just give the result a day later. Fighting with customers expectations is sometimes very hard.