Lemmy format allows having an actual dialogue
It’s great for seeing existing dialogue, but I think it falls short for long term discussion between more than two people.
On a non-threaded board (e.g. forums, github issues) you can watch a thread you’re interested in. On Lemmy/reddit you only get notifications for direct responses to your comments.
I think some sort of option to watch/unwatch whole subtrees of comments would help a lot.
It sounds like you’d benefit from having a project in mind. I always learned programming languages by building something I wanted, or by tinkering on someone else’s project.