This kinda looks like a father to son comparison from down the ages.

Well if Ledger's Joker is "edgy" then it was an example of "edgy done right." He wasn't "tryhard" like a Rob Liefeld villain (or hero for that matter), he came off some someone to be afraid of for how truly unstable he was, guy cared more about chaos than trying to gain power or wealth, and once he gained an obsession with ol' Bats he basically tortured him in every way he could aside from physical torture.