As per this post, it seems Lemmy World is having federation issues. I've had some of my posts and comments get suspiciously low response, so I've looked into it and it turns out that many of them aren't showing on other instances.
Here's an example: my Payday 3 post is only visible on Lemmy.world:
Meanwhile, in other instances, it doesn't show up at all:
It's not clear if this issue is exclusive to this instance but I thought I'd give people a heads up. I reposted and now it showed up in other instances. If you feel like you're getting no response from other communities, check on another instance if your content is visible, otherwise repost it.
I'm very new to Lemmy and have already been experiencing this problem just testing how commenting to a federated community on another server works. It doesn't/hasn't worked for me yet in controlled testing. I've been assuming it was a problem with the other lemmy instance where the community is created/hosted but now I'm rethinking that assumption.
Usually, not assigning sufficient resources at a workload just causes the backlog queue to get longer, but in the case of lemmy it seems to result in some items never getting processed at all. That's an odd behavior for a backlog to have.