Not OP but I have experience in private sector here - Deanonymization in private sectors is used by anti-fraud or brand protection systems. For example, in brand protection we identify same IP/scam infringer across multiple store fronts and then we can shut them down directly or get more certainty on their other posts. i.e. if it's a known infringer their scam likelyhood score goes up on all of their listings. So deanonymization doesn't have to point to exact real identity - just enough certainty to tie multiple entries together and then other systems can take it further like OP's manual review tho LLMs can obviously do a lot these days.