Bond Coupon Yield Why Is A Yield On A Coupon Bond Less Than A Zero Coupon Bond If Interest Rates Are Increasing?

Why is a yield on a coupon bond less than a zero coupon bond if interest rates are increasing? - bond coupon yield

The answer, he says, that performance was, on average, on-site. But can someone me a clearer explanation. I'm really confused. Let us assume that these were like Treasury bills. and the bonds are in the same year.