That is to say, I like to compare a room/channel/sub a bit like a cafe where you never know who is going to walk in. It might be nice folks looking for a pleasant discussion, but it could be drunken brawlers high on their drug of choice, or anything in between and in every kind of mental state you can imagine.
Usually it is some mix in a wide spectrum, and depending on the appeal, the crowd culture varies. Philosophical channels tend to be more naturally selective for civil debaters, but more political ones can be a mixed bag.
And just as you don’t want your bar to end in a riot and with broken tables and a bad rep, you absolutely need moderation. The paradox is solved if you keep the possibility of civil discourse, of speech and to be heard, as high as a priority as a mod as you can.
Stop doing it, and it starts leaning towards one way or the other, inclusionary for one group, exclusionary towards others.
When I modded I often had to take away the misconception that you had a right to be there. You don’t. You have the privilege to debate in the channel, not a right. And as a guest of the establishment you need be mindful of others, and abide by the rules who are not there to curtail your freedom of speech, but to provide well thought out debates.