Spongebob use to be a a bit nieve. But he was also mature in his own way. And accepted his mistakes.
But now he is a complete moron. And f***in cry baby.. And NEVER learns his lesson..
It use to be satifying to see Squidward get punished, when he deserves it. But now.. He DOSEN'T deserve it. And he gets punished even WORSE..
He use to be greedy, but also a good person, with a moral compass, and cares for Spongebob, father/son like. But now.. Krab's obsession of money is borderline psychotic. And he is willing to put Spongebob in danger just for a penny (heck, he fires him for a nickel)..
He use to be stupid, but loyal. Now he's stupid to the point he actually bullies Spongebob, and never gets punished..