What if he/she lives in a country where popcorn time is not illegal?
Your suggestion is not a practical one, but rather an opinionated one.
That used to be true for web browsers but IE got a major update. Now with less drive-bys and exploits.
Maybe it's because I'm on linux, but torrented content never gave me any viruses. So as far as I'm concerned, the legal stuff is more likely to infect your system with malware.