@Roundcat I've noticed the same and think I know why it is. In Mastodon, you have to search through the hashtags. On Kbin, you just have to be subscribed to a magazine which automatically pulls in posts with the same hashtag. It's easier to see things that way, especially if you have notifications on for the magazine.
They are just two different sorts of systems. Mastodon doesn't automatically give you anything. You have to do the digging yourself.