Case in point: if we had this conversation in real life, you would've cringed after I used the word "majority", and I would've immediately realized and corrected my poor choice of words. Without this feedback, I suspect that you were now under the impression that I am for the suppression of minority opinions. Which would've been the clickbait headline of the news coverage of this conversation if I were a minor celebrity, and this was Twitter/X.

Unpopular ideas are essential, but the tight feedback loop which the former physical constraints offered was still a useful component. It acts as a counterbalance to our tendency to let ideas and thoughts that are poorly developed, more damaging than they are useful, or just logically/factually flawed consume too much attention.

I know when I pay attention I notice that I can think a lot of ridiculous things, and it would take some gymnastics to arrive at the belief that every dumb little prejudiced / biased / flawed / incomplete thought is worth promoting to a global audience.

Sometimes an idea will have merit despite initially receiving bad feedback in the context where it was first voiced. That feedback is still helpful, though, and may prompt some refinement before it goes any further. Many ideas that don't have much merit die here, and that's a good thing.

The alternative is broadcasting it raw straight into the forever archives to be fought over and promoted based, at least partly, on how outrage inducing or divisive it might be, and it's my belief that we're worse off for this becoming more of a norm.

There are people who have no local access to a similar or understanding peer group. We often hear of this now in terms of sexual identity or preferences, but it could be anything from interests to skills or aptitudes to medical or psychological conditions. People go online to find community, especially community that's not represented locally.

(This, like The Force, has both a light and dark side, of course.)

There are also people who are distant from friends, family, or other community, and for whom online group interactions are among the few available options.

We read and hear now of the closely guarded and coded language that was used to refer to situations and circumstances in Victorian times. Slangs and argots arose to be able to communicate within an anti-society whilst excluding normies. People today may use similar methods (though tools for tracking slang, such as Urban Dictionary, tend to catch up quickly).

Technical means may help, as can anonymous or pseudonymous identities, though both these have their own serious limitations as I've described in other comments on this thread.

your points are of course good, but there exists private online groups where these risks are lower so especially friends and family are a non issue as there is no problem to have a private online conversation.

finding your community online is more difficult, but the point is not that you should avoid online groups, but that you need to be more careful how you communicate in online groups. you can't just hop in and spill your personal feelings without being aware of how those messages will be received. you want to get to know people first, and that takes more effort and time online than in person. it depends on what kind of people are in the group, and also if the group is public or private.

hackernews is public but most people are reasonable here and bad faith messages are not tolerated, so for a public group it is a pretty safe one, unlike twitter where you risk having your messages promoted to people with an unhelpful attitude.

Evidence of this comes from the level and scale of information breaches: the US DoD, Department of State, Department of Justice, multiple states' attorneys general offices, the Russian Kremlin and military establishment generally (I have strong though as yet unsubstantiated belief that a key factor in Ukraine's success has been a near-total compromise of Russian communications channels). These are entities with a strong incentive to and capability for ensuring secure comms and data management ... and yet ... they're failing. The refugee family or abused mother or whistleblower ... stands little chance.

One of the criticisms of HN is that people are occasionally attacked for their expressed viewpoints, occasionally on-forum (though that's usually swiftly dealt with), more often off. I've seen some well-known and high-karma leaderboard profiles callously call for the death of entire groups of people. And there are sites which do kibbitz on "Orange Site" as they tend to call it, often criticizing its moderation or behaviours, but also conducting just the types of abuse you're describing.

HN also lacks some of the specific protections you describe. There's no private or limited spaces, direct messages, or similar mechanisms, by intent and design. There is the option of throwaway pseudonymous accounts, however, which helps somewhat.

Ironically you're replicating the phenomenon being described: taking something out of context, exaggerating it to the Nth degree, racing down the slippery slope, and using this to imply that OP is Hitler.