Thanks. However, my understanding is that simply chilling a validator isn’t a permanent solution.
If a validator still has enough backing (self-stake + nominations), then chilling them only removes them temporarily, they can simply become active again once they choose to resume validating.
As far as I understand, the only way to prevent this permanently would be through a runtime change that allows governance to remove or restrict their backing. It also makes me wonder why W3F and Parity don’t seem interested in helping remove validators with a documented history of abusive behavior from the active set.