Because the CCP understands network effects and first mover advantage. And they see a locally-owned social network that can be repurposed for government survei

Because the CCP understands network effects and first mover advantage. And they see a locally-owned social network that can be repurposed for government surveillance/control as a strategic priority. Facebook obeying the rules today is less important than Facebook being compliant with (and quiet about) whatever edict is handed down next year.