There are characters who are central to the setting, like Satanick, whose role, history, motivations, and relationships are barely understandable if you only read the main works (mind you, you only get to properly know who he is in the watgbs reboot and only in the bonus room). To fully understand them, you're often expected to dig through the wiki, old art, bonus comics, Q&As, streams, Twitter posts, and obscure side material.
I don't think the lore is bad. In fact, I think it's one of Funamusea's greatest strengths. But the way it's distributed is incredibly messy. Sometimes it feels less like following a narrative and more like assembling a puzzle from pieces scattered across the internet over the course of a decade.