Ten years ago, There were a number of posts that I would disagree with but upvote anyway, because they made me think. I haven't seen that in a long time. That kind of writing has disappeared.
What did that kind of writing look like? It stated a position, and gave reason to believe/accept that position, usually fairly concisely. Instead, now we see either just a bare statement of position (usually rather shrill), or appeal to authority.
The other thing we see much more is zealotry. Too many people are here to push an agenda, not to have a conversation. To steal a phrase from Patrick McClure, they're in "transmit-only mode". That's not a conversation even if you're in it. And if you're not in it, it's like walking into a war zone. Why would I want to go there? I'm not going to learn anything from either side. (OK, I might learn what their talking points are. But as a general rule, all sides' talking points are propaganda, and that's not worth listening to.)
I don't want to be in the middle of a propaganda war. I want reasonable conversations where people say interesting things. I used to find that here. I still do, sometimes, but far less often than I'd like.