The only outlier there is the record (10-6). I didn't predict the Bears record. I was predicting modest stats with mediocre talent on the OL and at WR. The 2019 Bills offense was 23rd in points and 24th in yards. Nobody is calling that a successful offense. I'm just saying, Fields can still take a step in the right direction with this supporting cast.
Stunting the growth of a QB is unproven. Burrow wasn't stunted by a terrible OL leading to a torn ACL. Watson had a bad OL and had a torn ACL as a rookie as well, AND was sacked the 5th most times in NFL history the following year, and he was fine (on the field). Josh Allen wasn't stunted with the group I posted. Jared Goff went 0-7, with the worst statistical season of the last decade as a rookie and still wasn't stunted. Only example you can really provide is David Carr.
Bottom line, if Fields is bad, it won't be because he didn't have enough OL and WR help. It will be because he is bad. I don't think he will be bad, thus I think he will put up respectable numbers. Again, not saying the offense will be a successful outlier. But I think he will show enough to take that big leap next year like those guys above did.