Address book, photographs/video of people I care about and holidays, personal diary, hobby projects, old letters/emails, stored passwords, archived bank statements/contracts/insurance and other important documents.
I think you are very unusual if you don't care about any of this.
Yes, I think it's unusual to not care about photographs/videos. I used to think that they were important and that I would want to revisit them some day. However, now when I'm old enough that I should it simply hasn't happened. They are just some files that I will never open.
Most administrative stuff, especially if it's in digital form anyway, can probably be recovered without too much hassle if it's lost. But you're right that most people have a bunch of stuff (not all of which is admittedly digital) they wouldn't want to lose.
I think you are very unusual if you don't care about any of this.