The way HN is moderated today to accept only quality content, in the similar way, HN can mandatories HTTPS. Then people will start porting sites to HTTPS soon. There will be a clash but it's for good.
For the same reason Hacker News doesn't categorically ban articles behind a paywall, provided a workaround exists.
And as has been mentioned elsewhere, it would probably be a net negative for quality since potentially good articles would be banned.