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?
Why not? As long as you have more than one copies, and you validate their integrity over time, it shouldn’t be a problem.