If you liked The Interview and you're asking me to justify my stance on why I thought it was bad, no answer I give will satisfy you. You'll either think I'm a big, joyless Grinch who's never heard of the word "fun," or you'll think the points I'm making are incorrect.
If you liked The Interview, that means that the premise doesn't look to you like an empty Rogan and Franco cash-grab. Franco's constant eyebrow-cocking and exaggerated body language don't strike you as annoying or unbelievable. If you liked The Interview, you probably don't mind the amount of screen time dedicated to the bit where Rogan hides a dildo-shaped ricin container inside his butt. The sequence in which Eminem comes out of the closet is not a gimmick. Rogan and Franco's fake plastic erections were funny. To you, Kim Jong-Un liking Margaritas and Katy Perry probably looks like a clever and new idea, and not just one of a tiny few mildly novel gags in a sea of stale dishwater. The pee and poo humor is probably just part of the charm as well. Rogan playing a role that is exactly identical to dozens of his previous roles probably doesn't bother you either. You probably enjoy most of Rogan's films and probably think Dumb and Dumber is an immortal comedy classic. And there's nothing wrong with any of that.
I just really, really hated The Interview, because all of those things did bother me. Because the script felt like it was written in a week and didn't endeavor to entertain or surprise anyone under the age of 16. Because before The Interview I didn't know Franco was capable of giving a "worst performance." Because I care about movies, and I don't like seeing cynical film producers churn out another stale, derivative, intelligence-destroying film we'll all forget about in a week just because they know they can, and I especially don't like it when circumstances like the Sony hack allow those producers to get away with it even more than they usually would by turning an albatross into a cultural landmark. Without the hack, Rogan and Goldberg would have to answer for a shitty, shitty movie. Now it's a freedom-of-speech issue, and the next one will be even worse.