From the perspective of him being a simple unsympathetic, petty, pure hate villain. Let me explain... Plenty of people who criticize Zamasu and how he is as to being “unsympathetic” and that his motive is supposed to resonate with us without looking into how that actually works. That he you aren’t supposed to sympathize with him or like him or his goal. From Zamasu’s entire motivation, I feel it had an appropriate amount nuance in the fact that his perspective is incredibly short-sighted and flawed. That his descent into killing mortals and doing all that there is a duality to him, his genuine hate for mortals and seeing them as a blight and the fact that he is a petty sociopath with clear mental health issues. He grows to hate Goku only because he bested him in a fight in front of barely an audience. He despises that a mortal even comes close to his power. And while I feel they should have highlighted his mental issues more early on into his development as to not have people misinterpret that he is supposed to be a “Sympathetic Altruist” or “Sympathetic Extremist” More the fact that he is a mentally unstable, twisted manchild with a petty excuse under “justice.” His psychotic facial expressions when he fights alone are great to show how batshit insane be actually is. This contrasts in some cases with Goku Black, in the with his Saiyan body he has redeemable traits such as an honorable need to grow stronger, he doesn’t monologue and like to hear himself talk, his sense of “justice” excuse is far less so and he lets his true madness unfold in a face that’s not his and along with his saiyan instincts in his body go as well. His charm from being that he doesn’t hold as many pretenses and just goes with it and just says “fuck it!” He is far more composed when beaten, competent and less petty. He has a charm to him and is far more likable. Zamasu himself has been shown to have an incredibly high sense of self-entitlement and that it is his duty as a god despite being told by the far more experienced and the fact that he has this feeling of him in the likes to him “playing god” ironically even though he himself actually is a god in the “Zero Mortals Plan.” You feel he has no right to do this and that this is not the answer as to him only just deciding to kill plenty of mortals from judging only one race the babarians. He is a complete hypocrite in the fact that he kills for a amusement as well under genuine sense of “Justice.” He blinds himself to his own hypocrisy with his sense of “justice.” He himself only admitting that he loves to hear himself talk, but feels it as his “godly right.” Zamasu’s Fusion serves to show far more of how he is more zamasu than ever before. This is where both his arrogance and his mental issues come to a head, his pettiness as well. All that I found pretty well executed if it wasn’t rushed to hell I would have enjoyed it far more. He is the edgey psychotic high-school shooter in the form of a god and I (personally, you can sympathize with his motive if you don’t view it as petty like I do) absolutely was rooting for Goku or someone else to wipe that smug grin off his damned face and shut up his monologues and I loved that feeling. For me personally on that reason alone I give him just as many points as a villain.