That is the older members like hero and legendary and others( except the newbies who spam the forum). They always comment on a post if they have knowledge about it and suggest in a right way to the topic creator.
Well, not all the hero and legendary are the same because there are several accounts that have been made a long time ago where merit does not exist yet. Besides, there are still some users who have been merit trading just for them to rank up and if it happens you saw one, you should report it. But you must not only focus on higher ranks though because there are lower ranks that are overshadowed and also been providing a contribution.
They do not go out from the topic and only share that information which they experienced before or learn from anywhere.
And that is how the forum should work because several members are only here for profit. If you have knowledge that you think everyone doesn't know then share it because they will do the same. Exchange of everyone's knowledge is a good trade after all.
When I learn a topic from this forum than I make a little research about the topic to learn. ( Is it good please suggest?)
No doubt, this is the best thing to do rather than creating a topic that is already been discussed. After reading some articles you must support it with little research for you to be able to completely understand it.