I do not disagree with you. When you learn the stuff, it is perfectly OK to explain equations with words and even write equations with words. But this is akin

I do not disagree with you. When you learn the stuff, it is perfectly OK to explain equations with words and even write equations with words. But this is akin to the comments of a program. Once you get down to work, in a professional setting, all mathematics uses single-letter variables (and I may add that all programming should do the same). I also agree with you that starting math with set theory is utterly ridiculous and even harmful. You should start with arithmetic and with geometry (obviously, using single-letter variables when needed).