luceos when or by whom is unknown.
While I understand Flarum team's point in keeping core as clean as possible and making interface as user friendly as possible, I need to say that you are missing one very important point. Flarum in its current condition is very admin/mod unfriendly. And if it's not a big problem for now, when most people use Flarum for testing purposes or to build small niche communities, it will be a mess when people will use it for big projects.
I'm using Flarum for about a year already, my forum have just about 50 members and still I need to use split/merge functionality almost every day. And if split extension more or less works, merge extension is pretty unusable and looks abandoned to me. Because of that I need to use some workarounds like merging big old topics into freshly splitted small topics and so on.
You can imagine what we have in the end. A lot of broken links, headaches every time when you need to split/merge something etc. In other words Flarum turns from great user-friendly platform in theory in a messy forum in real life, where admin doesn't have tools for keep it clean and users don't have tools to even search something they posted in a long topics some months ago.
So, it may be a good idea to keep core clean, but there should be a balance. And if "moderative extension" you mentioned will never be done by anyone, how people should use and maintain their Flarum forums?