Digital, no contest.
I'm an old guy and I've been buying and reading books for most of my life. I own thousands of them, filling up shelves and stacked on tables and cluttering everything, and that's even with the bulk of them in boxes in my garage. I love them and I love being surrounded by them, but they're a chore and a burden.
And I have a collection of almost as many ebooks, all in a few GB on a tablet.
So ebooks win on space and convenience.
As far as the actual process of reading goes, they're pretty close to the same, but ebooks have a bit of an edge. I have no issues with a screen, so words on a screen or words on paper are pretty much the same. Physical pages though are bound along one edge and flexible and generally at least subtly curved, while a screen is perfectly flat and evenly lit. Also, on a physical page, I'm stuck with whatever typeface is there, while with an ebook, I can scale it to whatever I want or even change the font or colors or whatever. so ebooks win there too.
And while I'm reading an ebook, I can search the text for any term or character name or phrase, so I can refresh myself on things or find a particular passage or whatever without laboriously thumbing through the pages, and I can switch over to a browser anytime to get background for anything or just look up a word.
And when I finish or drop an ebook, I can just tap the back arrow to go to my shelf, or switch over to an app or browser and go online, and find another one.
So... yeah. I really don't think there's one single thing that physical books do better than ebooks, other than serving as decoration - filling space on shelves.
Yeah - I don't even really understand how all of that works. I see that people apparently sincerely believe, but I have no idea how - what it is that goes on inside their brains that allows them to make that leap to actually believing.