Comment by JakeTheAndroid

They allow a limited subset of rules, with strict parameters of what logic is allowed. Unless you do something fancy with workers.

Also, the protection for this was removed in a recent update before the incident, so it wouldn't have had an impact if a customer did this until that protect was removed. So maybe a few weeks earlier they might have started seeing some problems. But again, I am pretty sure the logic in the rule that caused the issue isn't available to customers.