I agree with you about the communities and forums. Those take years to develop, even with promising options like Lemmy. Reddit became so popular there was a niche community for literally anything you can imagine. I hope the enthusiasm carries over and develops elsewhere/here.
I’m currently looking for this, and I don’t think Reddit has a feature that’s what this sounds like. On Facebook you can download all your data, photos, posts, comments, in one big pile. Closest thing I can find on Reddit (which only came up when I googled it externally) is a form you can submit to request what data Reddit has “about” your account. And they request 30 days processing time.
What if business and pleasure overlap 🤔