It depends what you consider "bad", on its own this season was alright, some really really bad dialogue but a decent 6 or 7 out of 10 in the end. Ending felt a bit hollow but there were some great moments, particularly Frank's end.
But when you consider Season 1 was fantastic, Season 2 is bad in comparison, a huge drop off in almost every area. It's not always a case of "everyone says its bad so I'll go along with that myself", this just was a really average season and you will read that from the critics, the fans and the new viewers. I'll remember Season 1 for many years, I doubt I will remember much from Season 2.
That difficult "2nd album", its tough to follow up something that was truly great, many have tried and failed but never mind. never mind, never mind.