I spend that amount of time on my computer easily but I am not just wasting myself..
I am either trading and earning crypto, dealing with a lot of numbers is good for my brain, or I am reading and educating myself...
If you are glued to a screen just to be zombie entertained then ya that's bad for you, bu not all uses of technology are..
I wouldn't be 1/10th as smart as I am today without all of the self education that I have done from being infront of a screen..
The fact is that if a person often encounters numbers and at the same time spends different computing equations with mini, then this is automatically remembered and a person can then even intuitively make calculations. Memory is severely broken.