Honestly, I can't fault for instance a Liverpool native for not wanting to name names. These are all extremely dangerous people; among the top of European organized crime. And even after indictment plenty are still powerful operating from prison. Locals have been whacked for not keeping their mouth shut... By comparison, in many ways these people are more dangerous in Europe these days than the Mob is in New York.
But it's not like they are required to testify at a trial or anything like that. Just somebody mentioning a name on a forum discussion, to understand better who we are talking about, isn't something a real crime boss would care about imo.