Uppercase and lowercase terminology [closed]

Uppercase and lowercase terminology I believe refer to the location of type on a typewriter, as nobody under the age of 35 has seen a typewriter, would it be more correct to use the words letters and capital letters? In a page of type I believe that approximately 97% are letters and approximately 3% are capital letters.

Upper/lower case goes back to when typographers set type by hand from lead slugs ("sorts"). Each sort had a single character in a single weight of a typeface at a specific size, like 18 pt. Times Roman. The sorts were kept in sorted in a specific way in drawers, called cases. When a page was being worked on, the two drawers of the font were pulled and laid out on a table. The capital letters' drawer, the upper case, was situated above the lower case.

When a case fell on the floor and the letters flew everywhere, the whole rest of the day would be spent putting everything back where it belongs. That typographer would be pretty angry, or literally out of sorts.

Just because a word derives from technology that's obsolete, that doesn't mean the word is obsolete. If you say young people have never seen a typewriter, I'll bet they've at least seen a picture of one. But it's doubtful the same can be said about a type case drawer, unless they saw one on Pinterest or in an antique store.

See also https://en.wikipedia.org/wiki/Letter_case