Reddit is easier to read (comment threading) and is text only, which is its unique value proposition. PhpBB forum, which I ironically use way more than Reddit these days, have almost no threading and limits to 10 posts per page with no hiding posts unless block all user posts, and ad banners everywhere.
But I welcome any return to self-hosting, even though most site require membership until a user can view full scale images.
Reddit comments can contain images that display with the text, without requiring a click to open. Previously it was text only, but that is no longer the case.
I don't know that this is always the case, or if it's a scale thing.
I remember great, classic forum threads with 100+ pages that would get referenced, maintained, etc. It felt like being put on the same level as everyone else in sequential order was a pretty even playing field. It also gave you the ability to summarize and respond to a few different comments at once instead of having to navigate multiple content threads.
That said, I don't know if forum discussions would work for r/funny posts at that scale. It's literally a consistent 10K comments, all junk pretty much. The number of pages would blow up constantly, and it would definitely be harder to navigate the reactions.
But I welcome any return to self-hosting, even though most site require membership until a user can view full scale images.