They can still claim self defence that they were attacked by a knife or a rock, changes nothing.
Right-wing politics is everything that promotes giving power of one group over the other. Giving the rich more power to own weapons, while taking it away from working class, is a right-wing idea, by definition. It is not right-wing to claim everybody should own weapons, it is right-wing to claim, only the rich, or only the state or only the white should own the weapons, while others are not allowed,
When black panters were around, they would just carry the weapons, to show that if some white nationalist attack, they will not just sit there. Now whenever cops see someone marching with a gun, to protect the union strike or whatever, they can just arrest them, without any shooting even occurring. While anyone backed by the rich, will be able to pass by police with AR 15 with no problem. Just imagine two groups that started as a peacful protest being face to face, while one group is heavily armed and other is not.