I think that if you want to avoid negativity in forums and group chats, you really need to stick to one’s that are moderated. We are lucky that in the Justin community, it is very well moderated.
Hey C.S.,
I can’t recall a single instance of nastiness here in the Justin Guitar Community… there are differences of opinion for sure, but they’re definitely not people being mean just to be mean. We’re collectively very kind, helpful & encouraging of each other - I’m pretty sure that the members here are a tolerant lot with generally good hearts! 
My 2 cents, anyway!
Tod
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