Because everybody is complaining to everybody else that they aren't discussing the real ethical problem. This is being pointed at OP as well as commenters. It makes conversations difficult to have because as soon as people start talking about one thing, somebody jumps in and says "but you aren't talking about the real problem".

I have also noticed this in other HN discussions. Everyone seems to assume everyone else agrees with their view on the topic and there is never any open discussion about it. Usually people just talk past each other and it's never pointed out.

Because it's much easier to have constructive outputs when you focus on a single problem with a clear definition. But people usually conflate multiple topics into single and take advantages from this intentional ambiguity, irrespective of whether you're a proponent or a critic.