i have seen that newbies is adopting the system of long article with valueless point, so it's encouraging and admirable to make post that is lesser and have meaning, it's not that I'm condemning a long article writers post but we should understand the concept that your content of post at first also understand the summary of your point.
I think this is mainly to the influence of other posters who share tons of useful information who get merited at the end. The only difference is, either newbies copy-paste something (plagiarism) from the internet or they share tons of information which are not relevant at all.
Like what you have mentioned, even a short-reply but with meaningful and useful information can do the trick as long as you're focusing on the point of the thread. While this may take some time for some newbies to learn, all small-steps are big achievements on their own.