With the exception of Wilson, those are mostly the type of above average QBs that teams used to routinely sign to big money long term deals. The NFL as a whole has moved away from that plan. (That said, none of the contracts look too ugly now. The Seahawks and Eagles got some nice picks. Las Vegas only has $5.6M dead cap from Carr. Tannehill and Goff will probably be retained as their team's best available options.)
Wilson used a top QB, so he's the best comparison for Lamar. Once QBs attain that status there will always be teams willing to give up serious picks to see if they can make him work. Even Wentz, who only really had one great season, and has an injury history, was traded for a 1 and 3 after his massive decline.
Lamar's status as a player who has been mentioned among the MVP favorites at some point in each of the last 4 seasons, would probably have a trade floor somewhere above Wentz, no matter how badly his performance may slide, provided the Ravens act quickly if/when it happens.