For me I had a stack dvd blanks left over, I decided to save a little bit of money and used them to back up folders of childhood photos, documents etc and place them inside their own jewel cases.
I do have a 2TB external HDD, But that I throw on LARGE steam game back ups and movies.
Sure, the “cloud” exists and I use that too but what if your intewebz goes down, good luck getting your backups until it’s back up.
What do you use? Optical media, tape drives etc?
M-Disc Blu-rays last a thousand years literally. It will outlive all of your other mediums a hundred-fold.