I'm not going to say he doesn't deserve it because when you look at the contracts being handed out he clearly deserves something in this ballpark. With that said, there is a reason people say things like, "he's a winner", "he comes up big in big moments", "he's clutch", etc. despite the fact that he is not an elite passer and is prone to long stretches of average to below average play.
That reason is because his defense and running game keeps games close or flat out wins them despite his average play, allowing him to come up with a few big plays despite being no better than average to above average in most games. Now that he has this huge contract the team won't be able to afford the same type of depth on defense with guys starting to come off their rookie deals or demanding more money.
The ultimate irony is that you have QB's like Eli, Flacco and now Wilson who win SB's on the backs of their defense/running games despite not being truly elite QB's, yet they get paid like an elite QB because of that SB, and then their teams cant afford to keep the very same reasons they won those SB's because of the contract they gave to the QB.
This will happen with Seattle in the near future, just give it time.