Here's the story of the exec explaining the decision to reinstate the account:
https://www.forbes.com/sites/mattnovak/2023/08/09/twitter-ex...
It seems reasonable to me that if someone is, for example, sharing a video of violence to protest or raise awareness about the violence, the situation isn't the same as someone who glorifies or celebrates it, then their account would be reinstated.
Once the mass media industry decides that it hates something they seem to take on the momentum of a typical mob.