There are two problems at play here.
We clearly have some deficiency that renders us unable to cope with modern devices, else others would be affected, and they aren't.
Then there are the devices, there are devices that are more or less of a problem to us susceptible people.
There will never be a unifying theory or narrative that explains all of the causes and effects, because we as humans are far too complex. As such, any attempts to reduce our problems to a rigid cause-effect relationship are going to fail. It is my understanding that we share a related defect, be it in the structure of our eyes, or the regions of our brain that process vision. But due to the innumerate differences between us, such as eye or brain structure, our symptoms and triggers differ. That does not mean there are not patterns, we have collectively identified risk factors, such as dithering, PWM & blue light.
Consider a common analogy, we all get the common cold, but we all experience it differently, albeit with common themes. This is because of innumerate and incomprehensible differences between us.
Like others, I am no doctor, but I do model degradation and deficiencies of engineering infrastructure for a living. Its generally best to approach this thing from a stochastic viewpoint owing to the inability to ever resolve cause and effect in a rigid way.