They lost five hall of famers and couldn't replace them bc they drafted poorly and couldn't replicate the drafting (Russ the LOB drafted outside of first round except Thomas) and good FA signings (Lynch) that got them there in the first place. Thats not due to the contract.
Seattle gave Wilson a record breaking contract. While Wilson is a great QB (A fact many Panther fans refuse to acknowledge) Seahawks reaching the Super Bowl twice was in large part due to a dominant defense and running attack. Today, Seahawks have neither and that is in large part to misallocation of assets (money) forcing them to go cheap in areas of need.