I don’t want to go all in on being a picture board, but sometimes it’s fun to scroll through some pictures. But also, like 90% of the preview images on links are just stupid header graphics, so it’s off by default. Now for some groups example previews can be enabled.
On the other hand, something that link-aggregator forum-style fediverse platforms can bring to the table, IMO, is being multi-modal relatively effortlessly by providing multiple UI “modes” on top of the same backend structure. Compared to something like mastodon and its relatively simple feed, link-aggregators or forums, with their tiered structure and longer more free-form posts, can become many things with just some adjustments on the front end.
I can imagine, for instance, a modality switch in the front end, specific maybe to a group/community or a post, which allows the user to view things in “picture board” mode, “blog” mode, “forum” mode … etc.