You can also have the RSS feed of Old Reddit bridged over - the feed link is the subreddit's link with .rss appended at the end (e.g. r/Starbound). Through microblogging platforms (tested on Mastodon), you can go through either @owner or @birb to have Reddit's posts shared in the fediverse. And on the threads platforms (e.g. Lemmy), only know about !meta, where you can request feeds to be tracked. Can't check lemmit.online from the other comment right now.