Well, I've only been here a little while, so there's probably a lot I haven't seen. But most of the people here seem fairly supportive and friendly to me. Even when they disagree, most seem to do it calmly and kindly. Once or twice, I've seen a post that seemed a little harsher to me, but nothing like what I've seen on some other forums or in some conversations on FB. I know it's partly the rules here that prevent it, but I think it's the (lovely, for the most part) people here, also.
As for me, I generally give a lot of thought to what I post and even preview it before I actually post it. Cuz we only have words here. As another poster said, we can't see facial expressions. And we can't really know the "tone" for sure, even if we think we do. So I'm very careful about my words, probably more so than if I were talking to a person face-to-face. I'm not afraid to disagree with someone - I don't think we should have to be - but I try to do even that with compassion, if I can.
Even so, sometimes after I've posted something, I reread it and think it sounds a little harsh and so forth. So I'm sure some people who come across as being a little "too blunt" don't realize how their posts sound. I certainly don't mind someone coming out and saying it if someone has hurt their feelings. If that person was me, I'd definitely be ready to apologize. I'm not here to hurt anyone.
OTOH, I don't worry too much if someone says something harsh to me on an Internet forum. Again, I have no way of knowing, most of the time, if they meant it to sound that way. And it's not as if we know each other IRL or are going to meet in person (unless we choose to, I suppose). So it may sting for the moment, but I generally get over it easily. Haven't encountered this here, though, I'm happy to say. Not so far, anyhow. 