>>149953603 (OP)
I've never watched a single episode or even a clip of Adventure Time, but it's one of my most hated shows in existence. I'll try to explain my reasoning:
1. I see Adventure Time as a major turning point in culture. Prior cartoons—even wacky, eccentric ones—had been written the same way for literal decades, with little adult jabs and male gaze stuff. Think back to when you watched something like Dexter's Lab, and there'd be a throwaday joke about some hot woman with long legs or something. Adventure Time changed all that. The writers were socially progressive and eschewed anything that would be seen as regressive.
2. Early on, the show was setting up a romance between Princess Bubblegum and Finn, but couldn't commit to it. They kept it ambiguous and up in the air, teasing fans and remaining noncommittal. Eventually, they made a hard decision to abandon it, completely derailing it and going in the opposite direction. The reason for this, of course, is the age gap. Basically, writers refrained from doing what they wanted because of moral concerns. This is a complete 180 from cartoon creators from the past, like Bruce Timm, who famously had "old guy dates his younger female employee" relationships, just because they found it hot.
3. The show makes Finn a complete jackass for no real reason other than he's a boy. This trope isn't exactly new, seeing as it goes back to the '80s at least. But the basic idea is that the white boy character is selfish, reckless, and shortsighted, making dumb decisions to appease his ego or emotional whims. That type of character is contrasted with a woman or non-white character, who acts kind and reasonable. Adventure Time does that a lot, but one of the most infamous examples is the whole thing with Finn crashing his relationship with the Fire Princess.
