I watched it last week...but that ending of The Penguin with Oz doing, well...IYKYK....I hated that it was done but loved it for the show. I like that the writers didn't pull any punches and really made him an irredeemable character (TBF there never really was even a glimmer of a redemption arc, but I'm glad they went full dark). As a viewer I could only root for him as an example of unhinged will to power.
Side note: I read DC's Prodigal Bird earlier this year and it is a good companion piece. I think he is a great character when not leaning into the cartoonish aspect.