Hacker news is probably one of the least important places to do this.
It has a high concentration of technical users, only supports public posts (where technical users will notice and comment on such urls), and has very active moderation.
Texting apps seem like the most important place to implement it... judging by the spam that I get.
That kind of attitude will put people off guard though. These things pop up in places where you least expect them. I agree it's less important than other places, but also would be nice for us to practice what we preach.
It has a high concentration of technical users, only supports public posts (where technical users will notice and comment on such urls), and has very active moderation.
Texting apps seem like the most important place to implement it... judging by the spam that I get.