Let's look at the big picture view:
This is incredibly OP as a skill; the mere presence of cop reports already give town an immense advantage over the scum.
And in a very deep sense, this OP role is bad for gameplay: when village gets their easy clears / easy scums, the need to scumhunt is absolutely abolished.
A scum counter-claiming cop only stacks the cards higher in town's favor, because it gives them a 50/50 for finding a scum.
In contrast, the vig is not given any special clues as to who to shoot. They generally can't and don't claim their role. This contrasting nature of the vig and cop means that, given one or the other, a game with 1 or more vigs will always have more intense "scum hunting" than a game with 1 or more cops. Mafia is a game of psychology. The most zealous fans of Mafia will insist that it is "scum hunting" that really defines the game, and the art of "scum hunting" is what demands talent and rewards skilled players. So for people who want to play genuinely interesting and challenging games of mafia, the need to remove cop is obvious.
I know, I know, the practice of "cop worship" is widespread in the mafia community. If my political & technical appeals to you about "killing cops" don't sway your opinion, let me finally resort to artistic appeals. Please listen to these elegies from marginalized communities with an open mind. Together, we can move past boot-licking and live in a better world by killing cops.