Is Brady good? Yes he is. Overrated? Maybe.
Couple of issues here:
First, even the idea of whether Brady is "good" is obviously subjective and up for debate. You say he's "good", I say he's a bit above average, which in my mind is below the level of "good". So it's all up to how you interpret things.
Second, and more importantly, there is NO QUESTION Brady is over rated.
EVEN IF I were to agree Brady was "good" in the first place (and I'm not), he's STILL over rated, because there is a vast difference between him being "good" and being "elite". The former is what he may or may not be, the latter is what he is presented as being by many people - that HUGE difference is what makes him over rated.
It's been said more than once that Brady is to Pats fans as Jeter is to Yanks fans.
Jeter is over rated, too, but not by nearly as much as Brady. They both get a lot more hype than they deserve.
Plus people always applaud Jeter for playing for one team his whole career. I think that's laughable. If he had come up with the Pirates, the Yankees still would have bought him from them anyway, so he wouldn't have played the whole career with one team.
Take away championships. Give Brady/Jeter the same career numbers in KC or Minnesota. Are they still looked at the same way? I don't think so.
They are over rated because their teams won titles and they play in big markets.
Also, if you took away championships, and then moved Brady to KC, (assuming he put up the same numbers) I would guess he'd be viewed similarly as he would in Boston.
Only because his hype is so massive that he is over rated everywhere, not just in NE.