This is speculation and I understand may not go down too well for most.
My take is that the Byrdes are actually, genuinely trying to escape the life of crime they have found themselves in. The scene where they accept Navarro's initial offer shows how naive they are. Wendy especially appears to have broken bad completely but if you look at it, she is constantly simply trying to stay alive long enough to exit. She does strategise that as they exit the Byrdes can benefit from this situation as well.
Now for the finale kicker;
THE BYRDES GO COMPLETELY STRAIGHT. They are out of it and have genuinely been trying to exit the whole time.
What Jonah does is shoot the cookie jar. The cookie jar is the goat - a symbol from ancient times of the scapegoat which was sent into the desert to relieve the community of sin. In this case, the goat is symbolic of the sin that the family cannot let go, especially Jonah who is clinging to the 'ideal' of Ben especially. But Ruth carried the scapegoat curse too for a time.
The cop holds onto the scapegoat to use against the Byrdes. But it has been gained illegally, so is actually useless to him.
Jonah shoots the goat, dispersing the curse. Wendy uses the foundation she has built for good - she has used the system against itself. Wendy actually rocks.
