Yoc IS.IS.IS a metric for some stocks. What is untrue about the math, the metric?
It has already been said upthread. When it comes to dividends, your stock does not know what you paid for it.
You cannot compute with dollars at two different points in time. It is not meaningful to divide today's dividend by the 10 years ago price.
If the stock pays $1 dividends and Sam bought 100 shares at 20 last week whereas Fred bought 100 shares at 10 five years ago---the stock still pays $1 dividend.
YOC doesn't matter because stocks do not pay yield, they pay a dividend. One share pays the same $1 regardless of the price you bought it for. Or regardless of how many years ago you bought it.
All YOC is, is a meaningless number to make you feel good.