The benefit to a forum is that posts with new comments move to the top. If a Reddit/Lemmy post gets a single new comment it may or may not be seen again by anyone except the OP or of the comment was a reply then to the op of the replied comment.

Lemmy does have this actually

New Comments: Bumps posts to the top when they are created or receive a new reply, analogous to the sorting of traditional forums

https://join-lemmy.org/docs/users/03-votes-and-ranking.html

and then there’s the “Active” sort, which is kind of a compromise

Active (default): Calculates a rank based on the score and time of the latest comment, with decay over time

It’s a little bit not-obvious that the top comments are from News@lemmy.world here

Maybe they should get a header just like all the other communities do for their sets of comments?

the comments from the other communities actually stand out more than the comments of the current community, due to the headers, without the header the comments just kinda blend in

It’s a lean, expressive sharding sandcube for testing and deploying large scale Woodchips playgrounds.