The way this sounds is that you are more concerned about politics as in people who take party positions and may feel excluded as a group when the majority of the community takes a different position. This is a slightly different issue i.e. party politics, and I think it is fine/a good thing, but it is also important to distinguish the two. This should essentially be under the same umbrella as personal attacks, as they are essentially the same thing.
I'd rather see HN go politics-free forever. Political discussions do not enjoy the same level of objectivity that technical and business discussions do. Frankly, it may be impossible to expect objectivity within political discussion because our political feelings are so deeply-held and tied to our individual upbringings, culture, and locale.
Unless HN can figure out how to give fair treatment to minority opinions, it's best to exclude these discussions entirely.
Are there any online communities where their political opinions match more with yours? Why don't you hang out there instead? I realize that's reinforcing an echo chamber, but it sounds like you're looking for more of an echo chamber, right?
> even though I have made my points in an informed and respectful way
Maybe an example of a time you made a point in an informed and respectful way only to be downvoted and derided would help clarify?
> Unless HN can figure out how to give fair treatment to minority opinions, it's best to exclude these discussions entirely.
I strongly disagree. I don't know what "fair treatment" means, but if enough people on the site feel a topic is worth talking about, we should talk about it. Specific incidences of abuse should be flagged, but again, it's hard for me to say one way or another without examples showing what you mean.
As to the overall question of whether politics should be allowed on HN, HN started as "Startup News". It's always been a site about entrepreneurship, mostly in the tech industry. Entrepreurship is intimately linked to politics in obvious and non-obvious ways. Politics has to do with taxes, healthcare, immigration, legality of certain types of research, market size and access, shifting demographic trends, financing sources, and much more.
Edit: I removed a final sentence because it's moot and doesn't add to my actual argument.
You should learn to take feedback less personally.
It doesn't feel good and I don't come here to feel like crap.
If someone uses emotionally charged language to denigrate you, then I think you have a valid complaint. But the interpretation you assign to a downvote is just that - your interpretation.