tirreno guy here, we develop an open-source fraud prevention / security platform (1).

Sometimes there is no clear explanation for fake account registration. Perhaps they were registered to be actively used in the future, as most fraud prevention techniques target new account registration and therefore old, aged accounts won't raise suspicion.

Slightly off-topic, but there are relatively new `services` that offer native brand mentions in reddit comments. Perhaps this will soon be available for HN as well, and warming up accounts might be needed for this purpose.

1. https://github.com/tirrenotechnologies/tirreno