I regard music, photos and video as extremely valuable, so that doesn’t apply to me.

I do too, but for me there are levels of importance and my backup strategy reflects that.

There are files I can't live without, files I don't want to lose (photos), and the rest.

Out of curiosity, what are examples of files you can't live without?

Encrypted password manager file Previous tax returns License key list 2fa backup codes

Losing any of these would not kill me, but some would be horribly painful.

2FA recovery codes, password manager backup, a few government documents, a few banking/legal documents.

"Can't live without" is hyperbole, but losing any of those things would be a pretty big blow and recovering from the loss would be difficult.

Almost all of my music is replaceable (rips from CDs, etc). Most of my video by size is DVD rips, but the photos and videos of my own are valueable.

Still less than 10% of my total storage, and easily backed up.

Music is in theory replaceable, but finding and repurchasing everything I've collected over the decades is impractical. Just remembering everything is impossible.

I've never heard that saying, but it's a good one. That's been my exact experience.