There is justified objection to pax deliberately slowing down the security process. But how about the airport authorities doing the same?
Clearly, there is x-ray equipment around that can easily handle packed bags. So why do security at some airports pi$$ everybody off by insisting on unpacking laptops? This is clearly deliberate obstruction. If they are indeed so keen on getting people moving, they can at least oblige by installing state-of-the-art x-ray machines.