worldbuilding doesn´t matter at all. It´s themes that are important as they inform the atmosphere the players basically engage with. Examples out of actual Modules: Barovia as a setting doesn´t matter that much. What does is the gloomy atmosphere and the mist as a plothook for the party to engage with. The Ten Towns of Ice Wind Dale don´t really matter. You could easily reflavor every town given in that adventure. What matters is the Snow, Cold and Isolation created BY the Frostmaiden that sets her up as the villain of the campaign. The same counts for Exandria Mercers creation by the way. The story in campaign 1 dictated a classic heroes tale. Therefore more classical villains were introduced that got their backdrops. Of course Whitestone became a gloomy ruined city with a corrupted dying tree in the middle of it and an ancient ruin beneath. There was a backdrop needed for the Necromancer Vampire combo that are the Briarwoods. Of course former minute cities the party had ventured to before were ruined by the Conclave. A group of ANCIENT Dragons warrants an apocalyptic response in world. Of Course the main villain of the Campaign and greatest Big Bad Vecna arose a primordial Titan and marched towards the classic City of Good Gods. Don´t get bogged down by Worldbuilding, 99% of the time the stuff you DO come up with only does so because you want it to. Like look, nobody should expect you as a DM to be Tolkien. Especially if you´re not getting PAID to DM. Just have fun. Make that stupid character that makes no sense. Lean into the stupid idea that every tree in your world has a face and can speak. Not because it´s actually important but because having your party sit around a campfire all tensed up just to have a dumb voice ask stupid questions from the side is funny af.