Stepping into a new System/School, Burrow started the season off (1st 3 games) only completing 46% of his passes. The next 5 games his percentage is up to 58% That's pretty remarkable improvement IMHO. (For the Season he is at 54.8%)
And while 58% doesn't win you any awards, it's a far cry from terrible.
EDIT: And for the record he is half a percentage point better than Lewerke and McSorley...
In those five games, he's thrown for four TDs, four picks. His average pass gains 6.9 yards. His average completion gains 11.8. That ain't great. Also worth noting, he's not the first grad transfer, and a lot have done just fine to start the season.
I wouldn't say he's been terrible. But he's not been particularly good. He's had moments, the ones you mentioned, but he hasn't been good (also, Lewerke and McSorley are both kind of in bad shape right now).
It's sort of a weird thing. He's been by most objective measures, not good. He's leading the No. 70 passing offense and No. 83 total offense in S&P, and that's lifted up by facing a bunch of good defenses. But it seems OSU fans really like him.
It strikes me as a case of "not my problems." When it's not your problem and you don't live it, you see the good. Barrett got called a sandbagger at one point because his bad was something you felt. An LSU fan will no doubt point out he couldn't lead the offense to a point in the season's biggest game and threw up a 91.6 rating against a kinda good UF team.