I haven't had much trouble focusing on reading on computers, my only expectation is for the device to be touch screen and a pressure sensitive pen. The touch screen makes moving through pages trivial (for casual reading on say, my kindle, I have the habit of laying back and just tapping with my nose to flip pages lol) and the pen makes it trivial to mark up more serious reading material. With paper books I tend to not be near them right when I need them, and tend to be too wary of just marking them up. With digital stuff, and all the syncing we have between devices these days, I pretty much always have multiple devices at hand where the material is accessible.

I do still prefer physical books for things like art, I find it easier to study it and understand how it's put together that way (maybe because a physical copy forces me to look at the piece as a whole, rather than getting distracted by and overfocusing on minute details that turn out to not matter until I grasp the whole structure). However, even there, once I do understand how to look at the art, I can go with the digital version just fine.