He's certainly good. A 5 Star recruit out of high school and may have been the #1 player in the country that year. Not much chance to play at Texas so far sitting behind an entrenched starter in Ewers but he looked good in a few games while Ewers was hurt.
Is he NFL franchise QB good? I don't think we know that yet. But he has everything you need to be a franchise QB. But he still needs a lot of development and not every great talent becomes a great QB.