That first wave of trolls
(paid or not) was amazing, this forum quickly made a massive shift away from productive, "quality" conversations.
There is still plenty of good content here, but it is harder to find now.
...
The first HUGE wave of negative trolls came in June 2011, so when you see "Hero Member" there is no guarantee they are here for positive reasons.
Surely they didn't stick around and make a post every fortnight to become a Hero member. It's rare that you see a Troll Hero member as well.
You can be completely away for over a year and still have made "Hero", but you are correct that many of them probably have lower activity levels.