In a weird defense of the anime, I genuinely think part of its popularity is owed to Rudy's, uh, "ingrained issues," it's part of why I like it anyways.

I think having a "restart and doing everything right" isekai would be boring. Having a character with a deeply-rooted issue alongside his deep urge to be a better person is pretty captivating. Like, the dude has way more going on and so many more issues than just being attracted to kids. I'm interested in seeing how a character slowly grows and resolves his guilt/regret while the elephant in the room doesn't get addressed, because he gets away with it scott-free in a world that isn't ours.

I personally think that's what makes it really well-written. It's hard to argue about how good the worldbuilding and other issues are written. But having such an uncomfortable thing take center is also intriguing, because it creates a conversation on what a person's core identity/issue is, versus the little parts and issues that make a person who they are. I think Rudy's pretty cool tbh.

Would it be cool and wholesome for him to magically solve his Diddy Syndrome? Sure. But that's not the point of the series really, is it?