In plain terms
The same input always produces the same output, and the output cannot be turned back into the input. That is what lets the state hand out deletion requests without handing out personal information. It also makes matching exact and unforgiving. A trailing space, an uppercase letter, an accent left in place, or a phone number in the wrong format produces a completely different string, and a completely different string does not match. There is no close, and no partial credit.
What it means for a registered broker
The work is in the standardization before the hash, not in the hash. Lowercasing, stripping accents and punctuation, folding special Latin characters, transliterating Greek and Cyrillic through the published mapping table, and normalizing phone numbers to E.164 all have to happen first, in the order the specification gives. Two of the six list types are composite: they hash the parts and then hash the result, so field order and delimiter matter as much as the characters do. Get any of it wrong and every match fails silently, which on a dashboard looks exactly like having no matches.