Earlier quoted context omitted.
To be sure, what you're hearing from that website is not coil whine (inductor phenomena), but mechanical resonance caused by piezoelectric effect on solid state MLCCs[1] charging/discharging in your monitor during frame refresh. [1] https://en.wikipedia.org/wiki/Ceramic_capacitor#Microphony
In common parlance, I'm not sure there's a distinction between coil whine and capacitor whine. That is probably not something you can distinguish without taking apart the component in question.
Disassembly may not be required to trace root cause with high probability depending on the type of hardware exhibiting the issue, e.g. on a laptop, manifests upon affixing power adapter (as some have described) or tracks display pattern (as parent link).