Flaw in that argument is that cameras more than pay for themselves- they contribute resources to Police forces. Some shortsighted forces pulled a lot of traffic patrols in favour of cameras, which funnilly enough, led to a rise in vehicular crime and accidents. That gets simplistically blamed on the prevalence of cameras but there's no direct connection- it's just bad policing. Just look at our hero Brunstrom.
My take- which I've said before, but jsut to save time
Is that cameras are OK, when used right, just that it's rare for them to be used right. In combination with appropriate speed limits I have no issues at all, but there's too many places where the speed limits are all to ****, and that encourages speeding- if that speed limit over there's plainly stupid, you're more likely to ignore it. And once you do it for that one, you're more likely to do it elsewhere.