I use computer and also write on paper a lot (I usually use a pencil rather than a pen, although some people prefer to use a pen). Writing on paper it can be done anywhere (and I commonly do in many places), and regardless of power outage, etc, and is also easier to give to someone else, than a computer (and do not have to worry about the incompatibility of computers, etc). I could also store them anywhere.

Also for calendar, you can write it on a paper if you have a calendar on the wall; and, if you want to write notes on a paper next to something that it is relevant to (e.g. program numbers on a radio), then you can do that.

Paper can also be reused (especially if you write on both sides) and recycled, and should be done more; even you might have spare paper that you can write notes, etc.

They also mention package materials. I do think that reusable packaging materials would be better. (Reusable stuff is better in general.)