Paper gets wet.

Some critters like to eat paper.

Paper burns.

Paper has weight.

Paper has volume.

If you leave your papers at home, you can't easily access them by logging in on someone else's papers.

Photocopying seems analogous to copying files at first, but consider the costs of photocopying something. In addition to the expensive machine, you need paper and toner...

> Paper burns.

It shreds too. This is a feature.

And bits can be zeroed just as much as paper can shred.

Bits are a hell of a lot more fickle. I can't ever know for sure what will happen to my data that thousands of companies have harvested online about me, even if I ask every one of them to delete it all.

I can't have machine learning algorithms run on my paper to target me ads, either.

Paper needs no battery.

Paper needs no network coverage (not Wi-Fi)

Weights compared:

iPhone 6 4.55 ounces

Paper notebook (example) 3 ounces

Summing up the risks of flood+fire+critters you have a fraction of the risk for "falling to ground and break screen"+theft+malfunctioning.

You'll need a pen or pencil, though.

Nobody wants to carry around paper everywhere they go.

It's very laborious to do statistical analysis on paper.

How much text can you fit on 94cm^3 of paper?