Kinda sounds like it might be easier to get away with if it was a crime and the burden of proof was higher

“I didn’t know the router Comcast gave me came with an unprotected ‘Guest’ network enabled by default. Someone in one of the other apartments must have been using it to download torrents”

Sounds like a reasonable doubt to me, I’m sure there’d be plenty of other explanations. Plus the work to retrieve everyone’s computers to investigate who actually downloaded it would be prohibitively intensive in anything other than the most extreme cases