I guess you can do good work even with garbage worldbuilding, but why would you want to?
What’s your problem with the Pillars setting? I was moderately underwhelmed with both games (particularly the first), but world-building was one of the few things I thought it actually did pretty well. Certainly better and more complex/nuanced than anything Microsoft would allow them to create were they to start over from scratch.
It's way too mundane. In a word, the problem with the Pillars setting is that it’s disenchanted. I wouldn’t describe the worldbuilding as nuanced or complex, it’s just very detailed, which is not necessarily a strength.
I appreciate Sawyer’s desire to create a grounded, logical, semi-realistic setting, but I think that kind of backdrop clashes with the imperatives of telling an epic fantasy story. And, like it or not, the story will end up being epic because that’s what the market wants. That’s one reason POE and Deadfire both feel sorta off: you have this clash of the titans level story about gods at war with each other and it’s stapled onto a fairly low fantasy world. In Deadfire the contrast between the main narrative and the setting is even more jarring.
The other reason to create something new? The big metaphysical mystery of the Pillars setting has already been solved. I was just reading an author explain that good worldbuilding details are like Chekhov’s gun. You leave them lying around and then later on there’s some payoff when they go bang. With Pillars, many of those guns have already been fired. And they’re the worst possible ones to shoot. I don’t want to know about the origin of the gods or how soul power makes magic work. Explaining these things only detracts from the setting by removing the mysterious and fantastical elements. It’s disenchanted in the most literal sense of the term.
Let me put it another way: why would you use the Pillars setting when you could create a whole new setting that’s purpose built for the new game? Why wed yourself to stuff that Josh and Eric pulled out of their asses when they were desperately trying to make POE? If you’re going to recycle a setting, it either needs to be really popular in its own right (Star Wars, Forgotten Realms, to a lesser extent Golarion and World of Darkness) or really, really cool (Fallout before Bethesda).
I thought the worldbuilding in Tyranny was miles ahead of POE and that game was put together by Obsidian’s B-team on a smaller budget (that was looted to help pay for Pillars). They didn’t even really finish Tyranny, but the setting, the story and even the gameplay mechanics are tied together in a way that’s very much absent in Pillars.