What you're describing may be an issue. I suspect it is a tiny minority of the speeding tickets written. The above poster is advocating for well advertised limits and automated ticketing. I think this is a very reasonable solution to an undeniable problem: driving is dangerous, speeding more so.
The situation your describing a contrived edge case and is not a valuable contribution to the discussion at this stage.
"Just don't speed" is, by and large, a very reasonable thing to ask of drivers.
I read the article second article, the first is paywalled. I still think cameras are a good solution. The argument in the article sounds a lot like "some police are bad, we shoud disband the police" or "some government officials are greedy, we should disband the government".
Frankly, it sounds like the real issue if that they have privitized the production and configuration of the traffic cameras. If there was legislation in place that ensured fair and consistent implementation of the devices much of the issues identified by the author would be moot.
Any system that we put in place to enforce rules can be abused by those in power, but that doesn't mean the system is bad or wrong. The reality again is that cars are dangerous, and I argue we should prioritize protecting the public.
It's easy to hop in a discussion and say "no that's bad", but a lot more productive to say "here's an alternative".