I am looking for curation and durable content here.

For me, Reddit was a curated source of information. You have these communities full of knowledgeable people. If you went into that community you'd either find the info you need, already asked and answered, or you could ask and get a good answer. Discord is just real-time chat. It has virtually no search engine find-ability, no categorising, tagging, or reasonable way to go back and find something someone asked a year ago that was answered perfectly. Many of the social media are really personal and 'now' oriented. I'm eating a donut. This person pissed me off. I'm getting married, etc. Video streaming platforms have individual creators, who often have a theme, but they don't have communities or top-down categorisation. And video sucks as a searchable archive. It's really hard to know that 17 minutes into this video with a clickbait title, there's a really useful nugget of information. But Reddit (and now its federated clones) is user-curated and categorised. If I jump into a Windows-oriented community, I won't find a bunch of Linux stuff. If I want to look at a sport or a hobby or politics, there's a place to go. But it's not one creator/curator. It's organic.