That's great until your device is weaponised against others (see: open HTTP proxies, open DNS resolvers, open SMTP servers, several billion IoT devices, and countless other examples)
Yes, in an ideal world, that might work but most people don't actually know they have malware. That's the point of the malware! And it's not like you can say "no internet for you until you replace your TV[0]" because that's an extremely quick way to the courts and a customer reputation below the toilet.
(Ignoring the "who pays for that?" question because that is a whole 'nother can of worms.)
[0] https://www.ibtimes.co.uk/fbi-google-disrupt-proxy-network-a...
It would be foolproof, maybe the most trustworthy system ever conceived.