>>6194516I think it's less of a lobotomy and more like shattering his idea of a better future across space and time. You know, the soul-crushing realization one tends to get when faced with horrific forces beyond their control. Zamasu will still hate mortals in many timelines, no doubt about that, but it will be the apathetic and defeated kind of hatred instead of the intense zealot kind. He'd have his misgivings, but would almost never act on them or possibly mellow out without that passion to exterminate all mortal life.
Basically, we beat his ass so hard it made him a marginally better person across reality.