Threads with blatant lies should be counted as spam

Because that's what they are. You can't have a legitimate discussion about changes or the game state if you attempt to start it by lying about the facts. The discussion just devolves into the OP getting proven wrong, or the thread getting a lot of unwarranted attention because too many people don't bother to read them and question the validity of the statements.

That isn't to say it's always cut-and-dry. Saying "Ryze needs nerfs" isn't spam if you explain yourself well in the body, perhaps referring to the overwhelming strength of his ultimate in professional play and how that needs to be adjusted so his other abilities can be un-nerfed.

But threads with titles that lie about a champion being overpowered, and have little more than a video clip that shows something like a blatant mistake by the player in a same-level, same-completed-items fight, shouldn't be taken seriously.