"Why is it when ever 'I' have fun.. It's wrong?" - Squidward..
Although he is now more of a jerk, it is not all his fault.
His annoyance with Spongebob and Patrick grew larger and larger with each season. But in his defense. Spongebob and Patrick's stupidity increased more and more with each season, and they always break into his house when he's trying to enjoy alone time..
Mr. Krabs also blackmails him to work and barely pays him anything.
Whenever he tries to make any piece of art, he gets turned down for something far less well designed.
Though Squidward DOSE do bad things, he usually gets far worse punishment than what he deserves.
Many episodes focus on Squidward doing next to nothing antagonistic but still suffer from being maimed, tormented, or even having his hopes and dreams squashed. These episodes have been coined by MoBrosStudios as Squidward Torture Porns. These types of episodes have caused many fans of the show to sympathize with Squidward and because of heavy flanderization, made many see Squidward as the only likable character left on the show, until Squidward crossed the Moral Event Horizon in Little Yellow Book.