From an Addlerian perspective on human psychology of will to power, it seems that the anonymity of the internet with little to no threat of physical retaliation for bad behavior spurs on the zeroes to act tyrannical. In real life, these zeroes have nothing, so they create an online persona to battle for their fragile egoes. Precisely because of their lack of power in reality, the zeroes invest their limited resources online to pursue power in fantasy.
I find that often this is the case for many such tyrants even the ones that are legitimately powerful. There seems to be a fragile ego wanting attention in all of them.