I agree to disagree. First, you are right that they (most of shit-posters, spammers don't have ability to write good- (not high-) quality threads because they are lack of knowledge, skills, experience. Most of the time they spent in the forum till now is for spamming with shitty posts. They don't care about knowledge, skills, then that's why they are lack of them.
But you are wrong at the following point. Right atittude is the first thing to change so many things. It's Knowledge-Attitude-Practice relationship. Changing attitude first, then getting more knowledge, and finally changing their practices by composing high-quality, constructive threads.
Additionally, part of them have knowledge, skills, experience, by which I mean only small part of them are able to write high-quality posts, but they didnt' because they have no time to write such constructive posts (they are account-farmers so dont' have too much time for each account).
It doesn't depend so much on attitude as much as linguistic ability and how stupid and lazy these shitposters are. Even if they're now extremely motivated to write very interesting, well-written posts, most of them just don't have the ability to do so.