Yes, but Rush has also shown that he does not have an NFL arm. Rush is Ken Dorsey. Same guy.
Define better. Does better mean more talented? Does it mean better right now? Rush might be a better QB right now, yes. However, Grier has the arm talent to play NFL QB. Can he? Man, impossible to know at this point. He was fairly highly regarded coming in. CAR is a mess, but Grier quite simply got caught up in a numbers game at CAR. W/ Darnold as the starter and PJ Walker entrenched as the coaches fav backup, the Panthers took Corral in the 22 draft, leaving Grier in the cold. Grier was never given a chance to develop at CAR. Can he develop? That is the question, but he won't develop if he doesn't play. He comes from the WV O, which if I'm not mistaken is rather gimmicky, which means he'll have a pretty big learning curve.
College stats and draft position are irrelevant.