It depends entirely on the people participating and their willingness to separate themselves from their own ideas, so that attacking an idea isn't attacking THEM, as an individual. This also helps to just admit when you got something wrong, or more importantly, when you misunderstood someone's position, which is a lot more common. The thing is, there's also the type of people who think that the discussion forum is their personal blog, which makes things really hard since they have no interest in, well, discussing. It's parroting a position, or being highly combative. This kind of zero-sum mentality ends poorly for both the thread and the community in general.
There's a reason why in the guidelines I wrote 12 years ago there's this bit:
This is a reference to an actual dude who showed up once and that was his main argument. He'd basically invade miscellaneous threads and post about how it's all garbage except for music written before 1740 (or some other highly specific date, I don't remember exactly.) He got banned shortly after for being disruptive. We've had this, and we've had all sorts of stuff over the years.
But in the end, like I said before, if we're civil and nice to each other, we can get over all that stuff and have a good community that values and respects its members, even if people disagree on things. Back then we had quite a variety of different people holding different view points, and besides some banter, we were all still there. And for the few of us who remain, I really wish we can get something like that going again.