Yes, but you don't see new comments, plus this would be for posts and comments. If you just hide a comment, you don't see new replies. Marking as read is useful.
As it is, you only see new comments if you scroll past the post again (and your client has refreshed it) or if you open it directly. If your client hasn’t updated the comment count or if you refresh your feed and the post falls off, you’ll never see it anyway.
A “Watch” feature would solve this better. If you watch a post, you get aggregated notifications for edits and comments on the post. If you watch a comment, you get aggregated notifications for replies to it or any of its children.
By aggregated notifications, I mean that you’d get one notification that said “The post you watched has been edited; 5 new comments” rather than a notification for each new comment.
Then, in addition to exposing a “Watch” action on posts and comments, clients could also enable users to automatically hide posts that are watched, either by marking them as hidden or by hiding watched posts without updates.
If the latter approach were taken, notifications might not even be necessary - the post could just get added back into the user’s feed when changes were made. It would result in a similar experience to forums, where new activity in a topic would bump it to the front, but it would only impact the people who were watching it.
You can kinda get that behavior by sorting your feed by Active, but this could be used with other sorting methods.
Well, I've turned on that feature as a test (after the question was posted) and I saw your reply just fine. That's no difference from how it's been before I turned on the feature.
What has never worked for me (I'm not sure if it's a bug or by design) is a notification for a reply to your reply. I only ever see notifications of direct replies, not indirect ones.
In other words, if someone replies directly to me, I know about it, but if someone replies to that reply, I don't.
There is a open issue , the developers talked about it but no one pulled the trigger on it, this can be implemented on the client in a way that is pretty good (you could create client side backups using something like dropbox). We could open more issues on the various lemmy clients and maybe even piefed which seems to prioritize feature development in a way that might be better then lemmy developers currently. you can already read the comments on piefed and then subscribe to the posts and incrementally read new comments.