Yes, the letters used to be a pure scare tactic and the state was not giving a shit about it. A couple of years back they played in the hands of these kind of lawyers and debt collection firms by changing our laws in their favor. If you get letters these days they can actually fuck you over and it can go as far as ending up in court so ignoring the letters these days isn't the smartest option anymore. I ignore them because i, uh, handle my finances differently than the average German and am not in danger of getting forced to pay shit, if they can't prove that you have money they can do absolutely nothing. They will never see money from me, pure principle, and because Homeland was kinda shitty
I got a family member who pirated Oblivion from some public tracker as a kid and his parents paid roughly 1000€ when they got a letter over it so your friend is by far not the only person who fell for this stuff.