Cousins is weird. He is so talented, but usually good to great players on crappy teams put up better stats than he does. Love, for instance, was much better on a shitty Wolves team. Even if we attribute some of his crappiness to date to the Sacramento organization (and I think we should) does it make up enough of the gap to where he's actually good?
I really don't know. I'd love for him to be traded just so we can find out, though. What I do know is that it will never happen in Sacramento.
It really depends on what the player's strengths are whether they can be successful on bad teams or not.
In the Kevin love example, his strengths are rebounding and shooting, which are about as team independent as skills can get. Cousins rebounding numbers have been consistently great as well.
Cousins skills are ball handling and passing, but the team uses him most in shitty iso situations that force him to go 1 on 2 or 3 because everyone on his team is just watching instead of working to get open. Not that anyone else on his team is a good enough offensive threat to even worry the defense, so they could collapse on Cousins inside even if it left the perimeter open.
Generally ball dominant post players improve on better teams because they can pass out of the post when the play isn't there. Look at Blatche on the Nets this year for instance.
That's assuming Cousins even gets the ball on the post. Half the time he receives the ball out on the wing near the three point and his teammates expect him to get to the rim on his own, which often results in a bad jump shot.
Which is not to say that Cousins is not also responsible for all of these issues, there are plenty of things he could be doing that he isn't, but he is clearly not being used the way he should be.