It is very confusing because typically the previous generation’s i7 performs the same as the current gen’s i5, within the same tdp tier, and i5’s from a higher tdp can vastly outperform i7’s from a lower tdp within the same generation. Typically at any one time there are two or three processor generations in actual laptops being sold, as well as three or more tdp classes, so there is basically no good way of knowing how different laptops in the store compare performance-wise except by looking up benchmarks.