why do so many discussions turn contentious?

just venting....why do so many discussion posts need to turn  contenious and nasty?  do you guys find that constructive and/or enjoyable?  I have no clue who or how this forum is moderated, but I sure would love to see a stop to that...it makes me feel like this hobby is dominated by total jerks.

Can't we play nice, share OPINIONS and OBSERVATIONS, realizing that  they often are subjective and biased.  
"if you dont have anything nice to say, say nothing"?  If you wish to disagree, do it in a constructive and mature fashion, no need for "argument ad hominem"...

with all the chaff, one must waste so much time finding the wheat, figuratively speaking.  

I doubt my writing this will change anything, but, like most social media, people writing to others without facing them does not bring out the best, sadly......

In our culture, I think that civil discourse is becoming an historical artifact.
Much of this discourse thrives on the passive aggressive nature as well as anonymity. Social Media........Post things you would never say face to face.  
Audiogon is hurting their brand. Either the ought to moderate the discussions, remove them entirely or set it up so if a member asks a question all responses go directly to that member. No more public discussion. The anonymity afforded by these internet discussions has become an outlet for sick people. Fortunately for me the questions I have posted did receive some thoughtful and helpful responses; it is not all bad
Could this be more about the characteristics of personal belief than of science?  The same basic issues of religion and empiricism?