Because a few movies did "tragic villain" decently, audiences liked the switch-up, and the talentless hacks took it to mean that ever villain has to be "complex".
Those writers completely miss the point that the best sympathetic villains are the ones where their feelings of anger or other emotions that made them this way are somewhat justified, but the actions they take because of them are definitely not.
Because a few movies did "tragic villain" decently, audiences liked the switch-up, and the talentless hacks took it to mean that ever villain has to be "complex".
Those writers completely miss the point that the best sympathetic villains are the ones where their feelings of anger or other emotions that made them this way are somewhat justified, but the actions they take because of them are definitely not.
Nero from the first ST reboot was this. "my family/planet was lost: go crazy and waste everybody"