He has not the most yards or the most TDs in career
He has not the best passer rating, or passing percentage.
in fact, look for the passing records in the following
you will see that although Brady is mentioned a number of times, others such as Brees, Manning, Rodgers and a couple others are mentioned notably more.
His best stat in TD/int ratio, and he is only third in that.
What has he got going for him...6 rings. Maybe having a great defense and quality offensive players around him had something to do with that.