There are also practical considerations.
I much prefer physical textbooks but their bulk presents an issue. It's not fun hauling around one tome per class. I remember back in high school my backpack weighed 30+ lbs.
Last year I bought a 12.9 iPad pro as a textbook replacement. It works great (still miss the physical paper though). It has also greatly reduced the amount of weight on my shoulders during my bike commute to and from school. Nowadays I only carry my laptop and my tablet in my backpack.
Goodnotes can handle huge PDFs and enables me to write on and highlight the text. Voice Dream Reader is a great app to help slog through boring reading (Salli is the best voice I've found so far for scientific lit). I don't use Kindle-like ebooks for textbooks. Similar to what u/acconrad said, I need to be able to write on the text.
With all that in mind, my iPad pro is a designated READING device. I have notifications aggressively disabled for pretty much every app. No Facebook social media apps allowed. I won't/can't even log into Facebook on my web browser (someone else manages my password).