Yes he is. He's always been like that and has to be kept that way. Axon can't be redeemed since he's a cyborg and you said cyborgs can be reprogrammed and he was likely reprogrammed by Darkus to always hate everyone. Just accept it so Raxx doesn't become sad. And Raxx can't let Axon redeem himself because if that were to happen, Raxx would no longer trust you.
Why can't you be more like Raxx? If you understood him fully, you wouldn't be mad at him.