Piracy is still technically illegal but only a misdemeanor for the end user
(In the US) it's only a civil offense, ie they could sue you for damages, it's not a crime in the way most people use the word (misdemeanor or worse) - it can be a crime if you knowingly infringe copyright for profit. Otherwise it's civil.
no ISP has ever cared to narc about it
It's not that ISPs care what you're doing; they get a DMCA notice about a user and pass it on to the user. So the ISP just doesn't want to be seen as enabling the issue by ignoring the notice. The ISP isn't liable for what you're doing, as long as they don't claim it's non-infringing, or just ignoring the notice, or whatever. ISPs/companies don't want to be liable so generally they just pass along the notice.
It's just for distributing - so, you can download anything you want, basically, nobody is watching that. Download ROMs all day long, or whatever you want. It's just uploading that causes problems. So if you are using bittorrent and uploading what you download, you'll probably get a notice. Copyright holders can see that you are sharing something of theirs, and your IP address says what ISP provided your access, they complain to your ISP and your ISP says "you shouldn't do this," so they've passed along the note and maybe blocked your access until you click a button that says you received the note or whatever.
So you have to use a seedbox or VPN in a country that doesn't care about the DMCA. I use a seedbox, so I just have a computer in another country download/upload things. Whatever I download from the seedbox is encrypted and downloading isn't really policed anyway... all the uploading is in a country that doesn't care.
Check out https://github.com/massgravel/Microsoft-Activation-Scripts