Imagine this scenario: Copying and pasting a debug log, realizing it contains personal or important information (such as password, SSN, or anything else) and it is sent to the agent before you have a chance to redact that info. Or it could be accidentally pasting the wrong thing. I know that I've accidentally pasted Twitter links into my code before.
EDIT: Just to clarify my point. If you're going to break deeply entrenched user expectations, especially in ways that are often used maliciously: explicitly say you are subverting those expectations.
The same reason there are "This call may be recorded" messages when calling in, it shouldn't hurt much to add a "For quality assurance purposes, your keypresses may be logged in the chat window".
And if it does hurt, then you should realize your subversion is malicious.
Maybe you have more discipline, more sense of control and focus all the time. I don't and I know I am prone to making simplifying assumptions about things, because thats .. well .. human.
So.. I think either you are in denial about when you too make these kinds of mistakes "oh no: that only happens to other people, never happens to me" or .. you are a cyborg from the future.
I FOR ONE WELCOME OUR NON-FOOLABLE ROBOT OVERLORDS
https://en.wikipedia.org/wiki/Talk_(software) if you're on macOS, you have this command installed
http://mailman.postel.org/pipermail/internet-history/2002-De... (click on "Previous message" a few times too)
...but I recall that it was great fun (for about 5 minutes) answering questions before they had been fully typed and sent since I was the faster typist.
As you mentioned, I am shocked that the HN audience is shocked by this. I could see my parent's being surprised to discover this, but most HN readers should have figured this out a long time ago.
I remember plugins for various IM clients would do the same thing in a chat window some decades ago. And I remember my days as a sysop in the good old single line dial up BBS days. You could watch users browse and type all the way back in the mid-80's and I'm sure this has existed about as long as multi-user computers have.
If you're typing into an application which is any part of a networked or multi-user system, assume someone can see what you do while you're doing it (and can log same for later review).
...maybe I'm just old and don't understand the kids these days... or maybe it's a slow news day...