The Umbrella Corporation wrote:
Maybe nuKhan grew to love his people or realised he was alone without them in nuTrek. Marcus had a year to play mindtricks on Khan.
nuKhan was a completely different character. Like when he talks about his "savagery". Bull. Khan considered himself a superior being, and he was a leader, a despot, and Montalban's class conveyed that on screen, especially in Space Seed. There is no savagery in that.
'Superior' is a notoriously fuzzy concept.
It is quite believable that a conqueror/despot of half of Earth considers savagery to be a 'superior' trait; one quite consistent with having refined manners, being highly intelligent and a casanova, etc.